DE102017223600A1 - Method and apparatus for cleaning a material damage substrate - Google Patents

Abstract

The invention relates to a device and a method for cleaning at least one substrate (12) having at least one material damage (14), in which the substrate (12) is arranged in a reaction space (20) and cleaned in the reaction space (20), wherein:
- the substrate (12) in the reaction space (20) is subjected to at least one etching process for cleaning the substrate (12), and
- The substrate (12) in the reaction space (20) after the etching process is subjected to at least one deposition process.

Description

The invention relates to a method for cleaning a material damage having a substrate according to the preamble of claim 1. Furthermore, the invention relates to a device for cleaning a material damage having a substrate according to the preamble of claim 15th

Such a method and such a device for cleaning at least one at least one material damage substrate having, for example, already WO 2011/057829 A1 to be known as known. In the method, the substrate formed, for example, as a component or component of a technical device, in particular a technical device, is arranged in a reaction space of the device and cleaned in the reaction space.

Moreover, from the WO 2010/051174 A1 a system for cleaning a substrate is known.

The object of the present invention is to further develop a method and a device of the type mentioned above such that the substrate can be cleaned particularly advantageously and in particular can be prepared for repair following cleaning, without having to subject the substrate to excessively high temperatures.

This object is achieved by a method having the features of claim 1 and by a device having the features of claim 15. Advantageous embodiments with expedient developments of the invention are specified in the remaining claims.

A first aspect of the invention relates to a method for cleaning at least one at least one material damage such as a crack having substrate. The substrate is preferably a component or a component of a technical device, in particular a technical device or a technical machine. In particular, the substrate is, for example, a component of the turbine construction and thus, for example, a component or a component of a turbine, in particular a gas turbine. In the method, the substrate is placed in a reaction space and cleaned in the reaction space. The process according to the invention is thus a purification process. However, as will be explained in more detail below, the inventive method is not only a cleaning process, but in particular a preparation process, since by means of the method according to the invention not only cleaned the substrate, but also prepared, for example, for a subsequent repair to the cleaning, that is is made up. In particular, it is provided in the context of the method according to the invention that the formed, for example, as a crack or other material separation material damage cleaned and assembled, that is, for example, is prepared for a subsequent repair to the cleaning. As part of the repair, the material damage is repaired, for example, by the material damage, in particular the crack, for example, at least partially, in particular at least predominantly or completely, filled or repaired.

In order to be able to clean the substrate in a particularly advantageous manner and in particular to be able to prepare for a subsequent repair to the cleaning, without having to subject the substrate to excessively high temperatures, that is to heat excessively, it is provided according to the invention that the method has at least one etching process to which the component is subjected in the reaction space. In other words, the etching process is carried out at least once in the reaction space, so that the substrate is treated by means of the etching process while it is arranged in the reaction space. In particular, the etching process serves to clean the substrate, in particular the material damage. The etching process comprises a first step in which at least gaseous hydrogen fluoride and water vapor are introduced into the reaction space. Since the substrate in the reaction space is subjected to the etching process, the gaseous hydrogen fluoride and the water vapor are introduced into the reaction space while the substrate is in the reaction space.

The etching process and thus the method according to the invention furthermore comprise a second step, which is carried out after the first step. In the second step, at least one Sucking gas comprehensive fluid from the reaction space. Furthermore, the etching process comprises a third step, which is carried out after the second step. In the third step, gaseous trimethylaluminum is introduced into the reaction space. Furthermore, the etching process includes a fourth step, which is performed after the third step. In the fourth step, a fluid comprising at least one gas is sucked out of the reaction space. Furthermore, in the fourth step, the reaction space and the substrate are purged with at least one inert gas, in particular with nitrogen, for example, by introducing the inert gas into the reaction space and, if appropriate, then discharging or sucking it out of the reaction space.

In addition, the method according to the invention comprises at least one deposition process, to which the substrate is subjected in the reaction space after the etching process. In other words, the deposition process is performed at least once after the etching process, wherein the deposition process is performed in the reaction space while the substrate is in the reaction space. By means of the etching process, for example, the substrate, in particular the material damage, cleaned. By means of the deposition process, for example, the substrate, in particular the damage to the material, is prepared for the repair possibly following the cleaning.

The deposition process comprises a fifth step, in which at least one metal-containing vapor is introduced into the reaction space. Furthermore, the deposition process comprises a sixth step, which is performed after the fifth step. In the sixth step, a fluid comprising at least one gas is sucked out of the reaction space. Moreover, the deposition process comprises a seventh step, which is performed after the sixth step. In the seventh step, hydrogen is introduced into the reaction space. In addition, the deposition process includes an eighth step performed after the seventh step. In the eighth step, a fluid comprising at least one gas is sucked out of the reaction space. Furthermore, in the eighth step, the substrate and, for example, the reaction space are rinsed with at least one inert gas, in particular nitrogen.

The invention is based in particular on the following finding: Components or components such as, for example, high-temperature components of gas turbines can form material damage during operation, such as cracks, whose surfaces oxidize due to a hot gas atmosphere prevailing during operation in the gas turbine. Such a high-temperature component is, for example, a turbine blade of the gas turbine. In order, for example, not to have to completely replace the material damage described material damage component having a new component, the component is, for example, a structural repair or it is desired to subject the component of a structural repair, by means of which, for example, the material damage repaired or repaired or is corrected. The object of such a structural repair, which is to allow further use of the component or the component then repaired, is to seal material damage, in particular in the form of, for example, formed as cracks material separations and this maximum strength, preferably with the material properties of the substrate to to reach. For this purpose, for example, the crack is filled with repair material or closed. In order to achieve good strength properties, it is advantageous to remove oxides formed by the oxidation described above from the damage to the material, in particular from its surface, since otherwise no wetting of the substrate, which is also referred to as the base material, with the material formed, for example, as soldering or welding material and also as Repair material designated repair material can take place. Fracture mechanics, the cleaning of so-called crack tips is of particular importance, since just these areas must be closed for sustainable repair. At the same time, these areas are difficult to access geometrically and fluidically.

It is known from the prior art to carry out the cleaning in particular in the form of a deoxidation of damaged hot gas components in a separate process by means of hydrogen fluoride (HF) ion cleaning (FIC cleaning). In such a process is formed by an in situ reaction between a liquid or gaseous fluoride carrier and hydrogen fluoride (HF). Chlorofluorocarbon (CFC) or hydrofluorocarbon (HFC) compounds, for example tetrafluoroethane, also called freon, are used as fluoride carriers. To improve the process, a dispersion of fluorine-containing polymers, such as, for example, polytetrafluoroethylene (PTFE) having a particle size of approximately 100 micrometers, is infiltrated into the respective material damage, in particular as a crack. The PTFE serves as a fluoride donor. The in situ reactions to form hydrogen fluoride take place at 400 degrees Celsius to 1200 degrees Celsius. By-products are low hydrocarbons, such as methane, which react with water to form carbon monoxide and hydrogen. The water is formed during the conversion of metal oxides to metal fluorides. Some metal fluorides, such as molybdenum, tungsten and titanium fluorides, are volatile at low temperatures and can be removed by pumping through an absorbent. However, other metal fluorides, such as aluminum fluoride or chromium fluoride, require temperatures in excess of 1300 degrees Celsius. Can not substrates or components such as turbine components on heated to such high temperatures, these fluorides remain as impurities on the surface.

Furthermore, the conventional methods have the disadvantage that particles of a gas, a liquid and / or a melt must pass mainly by diffusion into the respective, for example, as cracks or narrow gaps formed material damage. During diffusion, the particles in the narrow gap move undirectedly due to their thermal energy and cover the substrate surface at random, so that it may not be possible to reach the entire surface of the material damage up to the aforementioned crack tips from the cleaning media. This allows impurities to remain on the surface to be repaired and provide for poor wetting of the repair material. In a subsequent repair brazing and / or repair welding caused by the impurities either pores or brittle metal oxide phases in the substrate, in particular in its material. In the further operation of the repaired component damage can occur again at these points, especially after a short time.

In order to obtain a particularly high strength during repair soldering or repair welding, however, very clean and highly conformal metal layers are needed. It has been found that these metal layers can be formed or realized by the method according to the invention and in particular by the combination of the etching process with the deposition process. The etching process and the deposition process are thus two processes which are combined with one another in the context of the method according to the invention, since the processes are carried out successively. The etching process enables stratified removal of oxides formed in particular by corrosion and / or corrosion damage. The deposition process allows a subsequent deposition of the at least one metal or metals, in particular in atomic layers, whereby, for example, the substrate particularly advantageous for a subsequent repair process, in particular in the form of repair brazes and / or repair welding prepared, that can be assembled. In this way, conformal layer deposits can be obtained on arbitrarily shaped substrates with a very high aspect ratio. The cleaning and finishing of the material damage of the substrate, for example, formed as a crack can be carried out in a plant or a device which also belongs to the invention.

It has proven to be particularly advantageous if, in the fifth step, the vapor has at least nickel (Ni) and / or cobalt (Co) as the metal. In this way, a particularly advantageous metal layer, in particular as an atomic layer, can be deposited on the substrate, in particular on the material damage, so that the substrate can be repaired particularly advantageously in particular subsequently.

In a particularly advantageous embodiment of the invention, in the fifth step, the vapor is obtained from a liquid solution of an at least metal-containing metal complex with aminidate ligands. In this way, the steam and thus the metal can be introduced into the reaction space particularly advantageously, wherein the metal can be deposited from the vapor in a particularly advantageous manner from the substrate. As a result, for example, a metal film can be formed on the substrate, in particular on its surface, from the metal, the metal film being formed in particular on a surface of the material damage. As a result, the material damage can be repaired for example particularly advantageous, in particular by the material damage, for example by repair brazing and / or repair welding with repair material at least partially, in particular at least predominantly or completely, filled and thus filled.

Another embodiment is characterized in that the solution comprises at least one anhydrous hydrocarbon in which the metal complex is dissolved with aminidate ligands. As a result, for example, unwanted oxidations can be avoided, which could be caused by water.

In order to be able to clean and assemble the substrate particularly advantageously, it is provided in a further embodiment of the invention that the vapor is recovered from the liquid solution in such a way that the solution is heated to or above its evaporation temperature, from which the vapor results or from the liquid Solution arises. In other words, by heating the solution, the steam is generated. The vapor is introduced into the reaction space in the fifth step together with a transport gas. At least one inert gas, in particular nitrogen, is preferably used as the transport gas. In other words, in this case, for example, nitrogen is used in particular as a transport or carrier gas, by means of which the vapor is transported from the liquid solution to and in particular into the reaction space and thus introduced into the reaction space. Here is the particular Steam mixed with the transport gas, so that, for example, the carrier gas and the vapor form a mixture or a stream that is or is introduced into the reaction space and thus flows into the reaction space. The nitrogen acts in particular as an inert gas to avoid undesirable reactions.

In a particularly advantageous embodiment of the invention, in the first step, the gaseous hydrogen fluoride is obtained from a hydrogen fluoride-pyridine complex having starting material. This starting material is also referred to as pyridine hydrofluoride, wherein the starting material or the hydrogen fluoride-pyridine complex has the CAS number 62778-11-4. The starting material preferably has exclusively the hydrogen fluoride-pyridine complex or consists exclusively of the hydrogen fluoride-pyridine complex, the hydrogen fluoride-pyridine complex or the starting material preferably comprises 30 mole percent of pyridine and 70 mole percent of hydrogen fluoride or 70 percent of hydrogen fluoride and to 30 percent pyridine.

Although pyridine hydrofluoride or the hydrogen fluoride-pyridine complex is toxic and corrosive, but is not as dangerous as gaseous hydrogen fluoride or hydrofluoric acid. In the following, gaseous hydrogen fluoride is also referred to as HF gas. Compared with pyridine hydrofluoride, hydrofluoric acid also has the disadvantage that it is an aqueous solution of gaseous hydrogen fluoride which boils at 112 degrees Celsius. This forms azeotropic mixtures. This means that the vapor has the same composition as the liquid phase (about 38 percent pure hydrogen fluoride and 62 percent water). Since water vapor is introduced into the reaction space in addition to or in addition to the HF gas, the dissolution of metal oxides on the substrate proceeds only very slowly and incompletely since the water vapor has an oxidizing effect opposite to the hydrogen fluoride. By contrast, pyridine hydrofluoride is anhydrous and splits off, for example, HF gas at 50 degrees Celsius, so that, for example, remains in a starting material receiving container such as a so-called bubbler after switching off of HF gas pyridine.

Thus, it has been found to be particularly advantageous if the gaseous hydrogen fluoride (HF gas) in such a way from the starting material, in particular from the Pyridinhydrofluorid (hydrogen fluoride-pyridine complex) is recovered, that the recorded in the aforementioned container starting material is heated in such a way in that the starting material splits off the gaseous hydrogen fluoride (HF gas) from pyridine. As a result, the disadvantages of already existing HF gas and hydrofluoric acid can be avoided, wherein HF gas can nevertheless be introduced into the reaction space and used for cleaning.

Another embodiment is characterized in that in the first step, the gaseous hydrogen fluoride is introduced into the reaction space with nitrogen. As already explained above with regard to the vapor, it may be provided to use the nitrogen as transport or carrier gas, by means of which the HF gas is transported into the reaction space and thus conducted. Here, for example, the nitrogen is mixed with the gaseous hydrogen fluoride or the nitrogen and the gaseous hydrogen fluoride form a stream, which is introduced into the reaction space and thus flows into the reaction space. For example, on the way from the container into the reaction space and / or into the reaction space, the nitrogen can act as an inert gas, for example in order to avoid undesired effects or reactions. In this way, the substrate can be cleaned particularly advantageous and prepared for any subsequent repair.

In order to be able to clean the substrate particularly efficiently and effectively and to be able to prepare for any subsequent repair, it is provided in a further embodiment of the invention that in the first step the reaction space and the substrate are heated to a predeterminable temperature, in particular actively. In particular, it is provided that, after heating, the reaction space and the substrate are maintained at the predeterminable temperature, in particular continuously. The predeterminable temperature is a process temperature which allows desired reactions to take place particularly advantageously.

It has proven to be particularly advantageous if the process temperature is in a range of from 300 degrees Celsius up to and including 400 degrees Celsius. As a result, the substrate can be cleaned and assembled particularly efficiently and effectively.

In order to be able to ensure, for example, a firm connection between the substrate and the repair material filling the material damage, it is provided in a further embodiment of the invention that in the deposition process, at least the metal from the vapor-containing layer is deposited on the substrate. The layer is preferably particularly thin and therefore also as a film designated. Since the layer comprises at least the metal from the vapor, the layer is, for example, a metal layer, in particular a metal film, which can function, for example, as a bonding layer. By way of example, the repair material can be connected to the substrate in a particularly advantageous manner via the connection layer, with the result that the substrate can be repaired particularly advantageously. In particular, the layer can act as a protective layer to protect the cleaned and, for example, metal oxide-freed substrate against oxidation and corrosion.

In order to avoid, for example, a lock and storage of the substrate in inert gas, in particular after the deposition, it is preferably provided that on the layer at least one at least one metal oxide further layer is deposited by a reaction of the vapor-derived metal with water vapor is effected so that the metal oxide of the further layer is formed from the vapor-derived metal.

In order to support, for example, the etching process and / or the deposition process and thus to proceed effectively and efficiently, it is provided in a further embodiment of the invention that ultrasonic vibrations of the substrate are effected at least during a part of the etching process and / or at least during part of the deposition process so that the substrate, at least during the part, carries out the induced ultrasonic vibrations, that is, oscillates with the ultrasonic vibrations. For effecting the ultrasonic vibrations of the substrate, for example, an ultrasound action is exerted on the substrate, wherein the etching process referred to as etching process and / or the deposition process, also referred to as deposition process, can be positively influenced by such ultrasound action. For example, cleaning, reducing gases and starting materials, in particular metal starting materials, can penetrate into very narrow or narrow regions and smallest angles of the substrate, in particular the damage to the material, for example as a crack, due to the effect of ultrasound. The ultrasound action or the ultrasonic vibrations can be effected, for example, by piezo elements and / or piezoceramics, which are installed, for example, in a substrate holder. By means of the substrate holder, for example, the substrate is held or supported during the etching process and during the deposition process in the reaction space.

In order to allow the etching process to proceed particularly effectively and efficiently, and thus to be able to clean the substrate particularly intensively, it is provided in a further embodiment of the invention that in the first step in the reaction space, in particular from the gaseous hydrogen fluoride, through Applying an electrical voltage, in particular an electrical high voltage, a plasma is formed. By the electrical voltage or by the plasma, which is formed for example from the HF gas and / or a different, additional plasma gas, the HF gas is ionized, whereby the plasma is formed. The plasma gas is introduced, for example, into the reaction space, whereupon the plasma is formed.

A second aspect of the invention relates to a device for cleaning at least one substrate having at least one material damage. Preferably, the device is designed to carry out a method according to the invention. The device has a reaction space in which the substrate can be arranged and cleaned. The reaction space is formed for example by a reactor of the device.

In order to clean the substrate particularly advantageously and in particular to be able to prepare for cleaning any subsequent repair process, which includes repair soldering and / or repair welding, for example, without having to heat the substrate excessively, it is provided according to the invention that the device at least one Provision and introduction device which is adapted to provide gaseous hydrogen fluoride (HF gas) and water vapor and to introduce it into the reaction space. Furthermore, the supply and introduction device is designed to provide gaseous trimethylaluminum and to introduce it into the reaction space. In addition, the supply and introduction device is designed to provide at least one metal-containing vapor and to introduce it into the reaction space. The provisioning and introduction device is furthermore designed to provide hydrogen and to introduce it into the reaction space. In addition, the supply and introduction means is adapted to provide nitrogen and to introduce into the reaction space, thereby to purge the reaction space and the substrate with the nitrogen. The device according to the invention further comprises a suction device, which is designed to suck a fluid comprising at least one gas from the reaction space. For example, unwanted components or reaction products can be removed from the reaction space by aspiration in order to avoid undesired reactions or effects, for example, in subsequent steps. Advantages and advantageous embodiments of the method according to the invention are to be regarded as advantages and advantageous embodiments of the device according to the invention and vice versa.

Further advantages, features and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the description of the figures and / or in the figures alone can be used not only in the respectively specified combination but also in other combinations or in isolation, without the scope of To leave invention.

• 1 eine schematische Seitenansicht einer erfindungsgemäßen Vorrichtung, welche zum Durchführen eines erfindungsgemäßen Verfahrens zum Reinigen wenigstens eines zumindest eine Materialschädigung aufweisenden Substrats ausgebildet ist;
• 2 die Strukturformel von HF X Pyridin;
• 3 eine schematische Darstellung eines Austauschs von Fluorid-Ionen gegen Methyl-Gruppen;
• 4 die Strukturformel eines Bis-Aminidat-Ligand mit zweiwertigem Metall;
• 5 eine weitere Strukturformel;
• 6 eine weitere Strukturformel;
• 7 eine chemische Reaktionsgleichung;
• 8 ausschnittsweise eine schematische und geschnittene Seitenansicht des Substrats, nachdem es dem Verfahren gemäß einer ersten Ausführungsform unterworfen wurde;
• 9 ausschnittsweise eine schematische und geschnittene Seitenansicht des Substrats, nachdem es dem Verfahren gemäß einer zweiten Ausführungsform unterzogen wurde; und
• 10 eine Reaktionsgleichung eines jeweiligen Metall-Amidinats mit Wasserdampf.

The drawing shows in:

• 1 a schematic side view of a device according to the invention, which is designed for performing a method according to the invention for cleaning at least one at least one material damage substrate having;
• 2 the structural formula of HF X pyridine;
• 3 a schematic representation of an exchange of fluoride ions for methyl groups;
• 4 the structural formula of a bis-aminidate ligand with divalent metal;
• 5 another structural formula;
• 6 another structural formula;
• 7 a chemical reaction equation;
• 8th 1, a schematic and sectional side view of the substrate after it has been subjected to the method according to a first embodiment;
• 9 1, a schematic and sectional side view of the substrate after it has been subjected to the method according to a second embodiment; and
• 10 a reaction equation of a respective metal amidinate with water vapor.

In the figures, identical or functionally identical elements are provided with the same reference numerals.

1 shows a schematic representation of a device 10 for cleaning at least one of 8th and 9 partially recognizable substrate 12 which - how out 1 . 8th and 9 recognizable, at least one material damage present in the form of a crack 14 or more cracks 14 having. The substrate 12 is for example a component or a component of a turbine, in particular a gas turbine. In this case, the component may be a component or a component which is exposed to particularly high temperatures or a gas having a particularly high temperature, for example during operation of the turbine. In particular, the component can be designed as a turbine blade of the turbine designed in particular as a gas turbine. How very good 8th and 9 can be seen, it is during operation of the turbine to the material damage referred to as material damage in the form of the crack 14 come. During operation, the crack can 14 , especially its surface 16 , oxidize what is caused or supported in particular by a prevailing during operation hot gas atmosphere.

In particular, thus, the substrate 12 in the area of the crack 14 on the surface 16 oxidize, so that oxides, especially in the form of metal oxides in the crack 14 or on the surface 16 can form.

For example, in order not to completely replace the component and replace it with a new component, it is desirable to subject the component to a structural repair, and thus a repair operation, in the framework of which, for example, the component (substrate 12 ) is repaired. Following this, for example, the repaired component can continue to be used so that the turbine can continue to operate with the repaired component. The task of the structural repair or the repair process is the crack 14 to close. The following and previous comments on the crack 14 Other material damage, in particular material separations, can also be transferred. For example, the crack 14 to be closed, this is at least partially, in particular at least predominantly or completely filled with a repair material, in particular by repair brazing and / or repair welding. In other words, for example, by repair brazing and / or by repair welding a repair material into the crack 14 introduced to close this. The repair material is thus a soldering and / or welding material. It is desirable when closing the crack 14 a maximum of strength, preferably with the material properties of the substrate 12 , to reach. To achieve sufficient strength values, however, it is advantageous to remove the aforementioned oxides from the surface 16 the crack 14 otherwise there is no wetting of the substrate, which is also referred to as the base material 12 can take place with the repair material or a particularly strong and intimate connection between the repair material and the substrate 12 to be able to guarantee. In particular, fracture mechanics is of particular importance for the cleaning of so-called crack tips, since it is precisely these areas that must be closed for sustainable repair. At the same time, these areas are difficult to access geometrically and fluidically.

Out 1 it can be seen that the device 10 a reactor 18 which, for example, a reaction space 20 the device 10 forms or limited and with a, in particular electrical, heating 22 Is provided. By means of heating 22 can the reaction space 20 , in particular active, heated or heated.

In addition, the device includes 10 a holding device 24 , which is also referred to as substrate holder or chuck. The holding device 24 is in the reaction space 20 arranged during the process, the substrate 12 , which is designed for example as a turbine blade, in the reaction space 20 on the holding device 24 is supported. In particular, the substrate becomes 12 by means of the holding device 24 held during the process, in particular in that, for example, the substrate 12 on the holding device 24 fixed, especially against the holding device 24 curious, is. For this purpose, the holding device comprises 24 For example, a clamping device, in particular a chuck. This means that the substrate is 12 with the crack to be cleaned 14 or with several, to be cleaned cracks, such as the crack 14 heard during the process in the reaction space 20 and while on the holding device 24 where, for example, the substrate 12 by means of a suitable device on or on the holding device 24 is held.

The holding device 24 preferably has a further, in particular electrical, heating, by means of which the substrate 12 can be heated or heated. The heating system 22 and the heating of the holding device 24 Thus, for example, are part of a heater or form a heater, by means of which the reaction space 20 and the substrate 12 can be heated or heated in the context of the process.

As will be explained in more detail below, the device 10 a provisioning and introduction device 26 which is adapted to provide gaseous hydrogen fluoride, water vapor, gaseous trimethylaluminum, a vapor having at least one metal, hydrogen and nitrogen and into the reaction space 20 initiate. Furthermore, the device comprises 10 a suction device 28 , which is adapted to at least one fluid comprising at least one gas from the reaction space 20 suck.

In particular, the device comprises 10 , in particular the provisioning and introduction device 26 , one or more so-called bubblers 30 with a plurality of valves 32a-h , Furthermore, the respective bubbler includes 30 for example, in each case 1 not shown containers. The gaseous hydrogen fluoride, the steam, the trimethylaluminum, the steam, the hydrogen and the nitrogen, for example, respective substances that can be received in the respective containers or provided by the respective containers. For example, via the valve 32a from the valve 32a associated container nitrogen, in particular in the gaseous state, provided and in the reaction space 20 be initiated. About the valve 32b and that the valve 32b associated container, for example, argon, in particular in the gaseous state, provided and in the reaction space 20 be initiated. About the valve 32c and that the valve 32c associated container, for example, the gaseous hydrogen fluoride also referred to as HF gas provided and into the reaction space 20 be initiated. About the valve 32d and that the valve 32d associated container can be provided, for example, the gaseous trimethylaluminum and into the reaction space 20 be initiated. About the valve 32e and that the valve 32e associated container, for example, the hydrogen, in the gaseous state, provided and in the reaction space 20 be initiated. About the valve 32f and that the valve 32f associated container, for example, a steam having at least nickel, that is, a so-called nickel precursor and provided in the reaction space 20 be initiated. Alternatively or additionally, for example via the valve 32g and that the valve 32g associated container provided at least cobalt steam and thus a cobalt precursor bereitgesellt and into the reaction space 20 be initiated. About the valve 32h and that the valve 32h associated container, for example, provided the aforementioned water vapor and into the reaction space 20 be initiated. The nitrogen, the argon, the HF gas, the trimethylaluminum, the hydrogen, the nickel precursor, the cobalt precursor and the water vapor are thus respective substances which are provided by means of the containers and, for example, from the containers via the valves 32a-h in the reaction space 20 can be initiated.

For this purpose, the respective substance forms, for example, a fluid flow, in particular a volume and / or mass flow, which flows via the respective valve 32a - H in the reaction space 20 can flow in. It can by means of the respective valve 32a - H a respective, in the reaction space 20 inflowing amount of the respective substance can be adjusted, so that in the reaction space 20 inflowing amount of the respective substance can be set specifically and as needed, in particular controlled or regulated, can be. The respective valve 32a - H For example, it is fluidic with one of the valves 32a - H common line 34 fluidly connected, which, for example, in the reaction space 20 empties. The respective substance can thus, for example, the line 34 flow through and over the line 34 in the reaction space 20 flow. In this case, for example, by means of the respective valve 32a -h a respective, the line 34 flowing through and thus over the line 34 in the reaction space 20 inflowing amount of the respective substance set, in particular regulated or controlled, be.

For this purpose, the device comprises 10 For example, an especially designed as a computer, electronic computing device 36 , The respective valve 32a - H can, for example, from the electronic computing device 36 be controlled or is from the electronic computing device 36 controlled, thereby by means of the respective valve 32a - H the respective, into the reaction space 20 to be able to adjust or adjust inflowing amount of the respective substance. To control the respective valve 32a - H represents, for example, the electronic computing device 36 at least one, in particular electrical, signal ready, which is also referred to as a drive signal. The respective valve 32a - H is thus regulated or controlled, in particular computer-controlled or computer-controlled, so that the respective substance is regulated or controlled, in particular computer-controlled or computer-controlled, into the reaction space 20 can be initiated. As a result, the respective substance can be particularly demand-oriented in the reaction space 20 be initiated.

For example, the nickel precursor and the cobalt precursor are also referred to as metal precursors. Besides, the line is 34 For example, a pipe or pipe system or part of such a pipe or pipe system, via which the respective substance from the respective bubbler 30 can be introduced into the reaction space. The bubbler 30 is also referred to as a bubbler system or as a vapor pressure saturator and is for example part of a plant for organometallic chemical vapor deposition and / or atomic layer deposition. Purpose of the bubbler 30 it is in particular, the respective precursors, also referred to as the starting material, in particular its organometallic compound or organometallic compounds to convert into a saturated vapor and this steam by means of introduced gas bubbles of an inert carrier or transport gas by entrainment controlled in the also called the reaction chamber reaction chamber 20 initiate. As the inert carrier or transport gas, for example, the hydrogen and / or argon and / or nitrogen is used.

As part of the process is in the reaction chamber 20 at least one etching process for cleaning the substrate 12 performed so that in the process the substrate 12 in the reaction space 20 is subjected to the etching process. The etching process is carried out, for example, at least once or more than once. After the etching process is in the context of the process in the reaction chamber 20 performed at least one deposition process, which is performed exactly or at least once or more times. Thus, the substrate becomes 12 in the reaction space 20 subjected to the etching process. As will be explained in more detail below, the etching process comprises a first step, in which the gaseous hydrogen fluoride (HF gas) and the water vapor in the reaction space 20 be initiated. In a second step of the method following the first step, a fluid comprising at least one gas is removed from the reaction space 20 sucked off, in particular by means of the suction device 28 , In a third step of the process following the second step, in particular the etching process, the gaseous trimethylaluminum is introduced into the reaction space 20 initiated. The etching process comprises a fourth step, which is carried out after the third step, and in the fourth step, a fluid comprising at least one gas from the reaction space 20 , in particular by means of the suction device 28 , sucked off, and the reaction space 20 and the substrate 12 are flushed with the nitrogen.

The deposition process comprises a fifth step, in which the aforementioned, the at least one metal having vapor, that is, at least one of the metal precursors, in the reaction space 20 is initiated. The deposition process comprises a sixth step, which is carried out after the fifth step, wherein in the sixth step, a fluid comprising at least one gas from the reaction space 20 by means of the suction device 28 is sucked off. The deposition process comprises a seventh step, which is performed after the sixth step. At the seventh step, the hydrogen enters the reaction space 20 initiated, whereupon in an eighth step of the deposition process, a fluid comprising at least one gas from the reaction space 20 by means of the suction device 28 is sucked off. In addition, at the eighth step, at least the substrate becomes 12 flushed with the nitrogen.

Preferably, before the first step by means of the suction device 28 an extraction carried out, in the context of which at least one gas comprising fluid from the reaction space 20 is sucked off. This extraction carried out before the first step ensures in particular that initially in the reaction space 20 located air before the beginning of the etching process also referred to as etching process from the reaction space 20 is sucked at least partially, in particular such that, for example, in the reaction space 20 a fine vacuum or a pressure of about 0.1 millibar prevails. The precursors, which are also referred to as starting materials, are in the liquid state in the bubbler 30 or in respective containers, in particular with the conclusion of air, oxygen and moisture. The respective precursor is used for etching the aforementioned metal oxides and for metal deposition. The precursors are organometallic compounds, and trimethylaluminum, in particular in liquid form, is also a precursor. The trimethylaluminum is also referred to as TMA or (CH3) 3A1. As the nickel precursor, for example, bis (N, N'-di-t-butylazetamidinato) nickel (II) is used, for example, as the cobalt precursor bis (N, N'-di-i-propylazetamidinato) cobalt (II) is used. As a fluoride precursor for providing the HF gas, for example, a starting material in the form of HF-pyridine is used, wherein the fluoride precursor initiates the etching of the metal oxides. The nitrogen and the argon serve as carrier gases, thus the precursors through the pipe 34 or through the pipe system in the reaction chamber, which is also referred to as the reaction chamber 20 be fed. In addition, the nitrogen and argon are used as purge gas to remove excess reactants and reaction products from the reaction space 20 used. For example, the gases nitrogen, argon and hydrogen come from a gas cylinder.

The respective containers in which the precursors are stored or recorded are, for example, components of the bubbler 30 or per se as a respective bubbler, wherein the respective bubbler is equipped, for example with at least one supply pipe and at least one discharge pipe. For example, nitrogen is introduced into the respective supply pipe, which then bubbles through the respective precursor. Furthermore, the respective precursor is heated in the respective bubbler, in particular by means of one, in particular electric, heating. In particular, the respective precursor is heated, for example, in such a way that a precursor vapor, also referred to as precursor vapor, is formed from the precursor. The precursor vapor mixes with the nitrogen introduced in a controlled manner into the respective bubbler, so that a mixture comprising the respective precursor vapor and the nitrogen is formed. This mixture of precursor vapor and nitrogen leaves the respective bubbler via the sampling tube and is via the pipe system or via the line 34 , in particular pneumatically, with the aid of the respective valve 32a-h in the downstream reaction space 20 and while on the substrate 12 directed. A respective temperature of the respective precursor in the respective bubbler is monitored or controlled, for example via a respective thermostat, so that a defined constant vapor pressure, in particular of the respective precursor vapor, is achieved. In this case, a respective pipe between the respective bubbler and the reaction space 20 have a higher temperature than the respective bubbler per se, so that the respective precursor or the precursor vapor on walls of the pipeline, by means of which the respective precursor or precursor vapor from the respective bubbler to the and in particular into the reaction space 20 is passed, not condensed and, in particular in liquid form, in the reaction space 20 on the substrate 12 drips. A controlled supply of the respective precursor or precursor vapor into the reaction space 20 takes place by a regulated flow of the nitrogen and by the temperature of the respective bubbler, from which the vapor pressure of the respective precursor or precursor vapor results.

The aforementioned etching process and the aforementioned deposition process are respective processes or steps, which processes include the removal of the metal oxides and the production of clean conformal metal layers to which the repair material formed, for example, as a soldering and / or welding material adheres particularly well.

In order to be able to remove the metal oxides particularly advantageously, for example, in particular in the first step, the reaction space 20 and the substrate 12 heated to a temperature which is preferably in a range of including 300 degrees Celsius up to and including 400 degrees Celsius. This temperature is a process temperature. After reaching the process temperature, the gaseous hydrogen fluoride, that is, the aforementioned HF gas into the reaction space with the aid of a nitrogen stream 20 over the substrate 12 directed. The HF gas originates from the fluoride precursor, also referred to as fluoride-containing precursor, which is preferably formed as HF X pyridine. This HF X pyridine is also referred to as pyridine hydrofluoride or as a hydrogen fluoride-pyridine complex and has, for example, the CAS number 62778-11-4. For example, the HF X pyridine consists of 70 percent hydrogen fluoride and 30 percent pyridine and has the in 2 Structural formula shown.

Although pyridine hydrofluoride is toxic and corrosive, it is not as dangerous as HF gas itself or hydrofluoric acid. Hydrofluoric acid also has the disadvantage that it is an aqueous solution of gaseous hydrogen fluoride which boils at 112 degrees Celsius. This forms azeotropic mixtures. This means that the vapor has the same composition as the liquid phase (about 38 percent pure HF and 62 percent water). In addition to or in addition to the HF gas also steam is still in the reaction chamber 20 initiated, so that the dissolution of the metal oxides is very slow and incomplete, the water vapor opposite to the HF acts oxidizing. By contrast, pyridine hydrofluoride is anhydrous and splits off HF gas at 50 degrees Celsius and remains in the respective bubbler as pyridine.

$$\text{B2O3}+6\text{HF}=\text{2BF3}+3\text{H2O}$$

$$\text{Cr2O3}+\text{6HF}=\text{2CrF3}+\text{3H2O}$$

$$\text{ZrO2}+4\text{HF}=\text{ZrF4}+2\text{H2O}$$

$$\text{TiO}2+4\text{HF}=\text{TiF}4+2\text{H2O}$$

$$\text{WO}3+6\text{HF}=\text{WF}6+3\text{H2O}$$

$$\text{MoO}3+6\text{HF}=\text{MoF}6+3\text{H2O}$$

$$\text{NiO}+2\text{HF}=\text{NiF2}+\text{H2O}$$

$$\text{CoO}+2\text{HF}=\text{CoF}2+\text{H2O}$$

As the introduction of the HF gas and thus into the reaction space 20 inflowing HF gas flow through the vapor pressure of the precursor and by the carrier gas in the form of nitrogen, in particular by its pressure, precisely by means of the electronic computing device 36 is set, in particular regulated or controlled, a monolayer of HF gas is applied to the metal oxide surface of the substrate 12 chemisorbed. The metal oxides are converted into metal fluorides according to the following equations: $$\text{AL2O3}+6\text{HF}=2\text{AlF3}+3\text{H2O}$$

$$\text{B2O3}+6\text{HF}=\text{2BF3}+3\text{H2O}$$

$$\text{Cr2O3}+\text{6HF}=\text{2CrF3}+\text{3H2O}$$

$$\text{ZrO2}+4\text{HF}=\text{ZrF4}+2\text{H2O}$$

$$\text{<figure-callout id="2" label="TiO" filenames="DE102017223600A1\_0018.png,DE102017223600A1\_0019.png" state="{{state}}">TiO</figure-callout>}2+4\text{HF}=\text{TiF}4+2\text{H2O}$$

$$\text{WHERE}3+6\text{HF}=\text{WF}6+3\text{H2O}$$

$$\text{<figure-callout id="3" label="MoO" filenames="DE102017223600A1\_0016.png,DE102017223600A1\_0017.png" state="{{state}}">MoO</figure-callout>}3+6\text{HF}=\text{MoF}6+3\text{H2O}$$

$$\text{NiO}+2\text{HF}=\text{NiF2}+\text{H2O}$$

$$\text{CoO}+2\text{HF}=\text{<figure-callout id="2" label="CoF" filenames="DE102017223600A1\_0018.png,DE102017223600A1\_0019.png" state="{{state}}">CoF</figure-callout>}2+\text{H2O}$$

Nickel superalloys, of which, for example, the aforementioned components are formed for gas turbines, wherein, for example, the substrate 12 is made of such a nickel superalloy, the elements mainly include nickel (Ni), cobalt (Co), aluminum (Al), tungsten (W), molybdenum (Mb), titanium (Ti), chromium (Cr), boron ( B) and zirconium (Zr). In particular, the oxides of these elements or metals are considered here.

Subsequently, for example, excess HF gas molecules and water vapor molecules and at 200 degrees Celsius to 400 degrees Celsius volatile fluorides such as molybdenum fluoride, tungsten fluoride, titanium fluoride and boron fluoride by means of the suction device 28 from the reaction space 20 aspirated, whereupon, for example, the reaction space 20 and the substrate 12 be purged with nitrogen. This is done especially in the second step. In the third step, gaseous trimethylaluminum is introduced into the reaction space 20 initiated. The trimethylaluminum is absorbed by the metal fluorides. In doing so, they react Metal fluorides with the trimethylaluminum by exchange of their ligands. The methyl group of the trimethylaluminum is exchanged for the fluoride ions of the metal fluorides, which in 3 is illustrated. This means in 3 g gaseous and f means solid. This gives rise to volatile AlF (CH 3) 2 and Me (CH 3) 3 compounds. For example, in the fourth step, the volatile AlF (CH 3) 2 and Me (CH 3) 3 compounds and excess trimethylaluminum from the reaction space 20 by means of the suction device 28 sucked off, and then become the substrate 12 and the reaction space 20 purged with nitrogen, the nitrogen in the reaction space 20 is initiated.

As described above, the first step, the second step, the third step and the fourth step are components of the etching process, also referred to as the etching cycle, or form the etching process, which can be repeated several times, for example. The respective step of the etching process is an exposure step, which in each case proceeds completely in the respective etching process, that is, the molecules of the hydrogen fluoride and the trimethylaluminum gas are chemisorbed and react with the oxygen atoms of the metal oxides and the fluoride atoms of the metal fluorides, to the oxide surface and the fluoride surface is fully occupied. Thereafter, no further adsorption processes take place on the oxide and fluoride surfaces. The etching process is self-limiting under these reaction conditions, that is, the amount of metal oxide etched in each reaction cycle is constant. The oxide layer to be etched decreases with each successive cycle.

$$\text{Cr203}+6\text{HF}+6\left(\text{CH3}\right)3\text{AI}=2\text{Cr}\left(\text{CH3}\right)3+6\left(\text{CH3}\right)2\text{FAI}+3\text{H20}$$

$$\text{Zr02}+\text{4HF}+4\left(\text{CH3}\right)\text{3AI}=\left(\text{CH3}\right)4\text{Zr}+4\left(\text{CH3}\right)2\text{FAI}+2\text{H20}$$

$$\text{NiO}+2\text{HF}+2\left(\text{CH3}\right)3\text{AI}=\left(\text{CH3}\right)2\text{Ni}+2\left(\text{CH3}\right)2\text{FAI}+\text{H20}$$

$$\text{CoO}+2\text{HF}+2\left(\text{CH3}\right)\text{3AI}=\left(\text{CH3}\right)2\text{Co}+2\left(\text{CH3}\right)2\text{FAI}+\text{H20}$$

The overall reaction of the etch process for the non-volatile metal fluorides is, for example: $$\text{Al203}+6\text{HF + 4}\left(\text{CH3}\right)3\text{AI}=6\left(\text{CH3}\right)2\text{FAI}+3\text{H20}$$

$$\text{Cr203}+6\text{HF}+6\left(\text{CH3}\right)3\text{AI}=2\text{Cr}\left(\text{CH3}\right)3+6\left(\text{CH3}\right)2\text{FAI}+3\text{H20}$$

$$\text{Zr02}+\text{4HF}+4\left(\text{CH3}\right)\text{3AI}=\left(\text{CH3}\right)4\text{Zr}+4\left(\text{CH3}\right)2\text{FAI}+2\text{H20}$$

$$\text{NiO}+2\text{HF}+2\left(\text{CH3}\right)3\text{AI}=\left(\text{CH3}\right)2\text{Ni}+2\left(\text{CH3}\right)2\text{FAI}+\text{H20}$$

$$\text{CoO}+2\text{HF}+2\left(\text{CH3}\right)\text{3AI}=\left(\text{CH3}\right)2\text{Co}+2\left(\text{CH3}\right)2\text{FAI}+\text{H20}$$

The number of necessary process cycles, the contact time of the Ätzreaktanten, as well as the quantity of HF gas and trimethylaluminum per unit area and cycle depends on the severity of material damage and thus crack depth and associated metal oxide thickness and reactivity of the material.

• Bis(N,N'-Di-t-Butylazetamidinato)Nickel(II), (99.99%-Ni)Puratrem
• Als der Kobalt-Präkursor wird beispielsweise verwendet: Bis(N,N'-Di-i-Propylazetamidinato)Kobalt(II),min.98%

The deposition process will be explained in more detail below. In the context of the deposition process, at least one protective layer, in particular formed as a metal layer, is deposited on the substrate 12 , especially on the crack 14 deposited, for example, this protective layer is formed from the vapor-derived metal. The purified and freed from the metal oxide substrate 12 remains in the reaction space 20 and is immediately provided with a thin metal film of cobalt and / or nickel for protection against oxidation and corrosion. This metal film is the aforesaid protective layer and is formed, for example, from cobalt-derived cobalt and / or nickel-derived nickel, by passing the steam comprising at least cobalt and / or the steam comprising at least nickel into the reaction space 20 is initiated. The nickel precursor and cobalt precursor are also referred to as metal precursors. In other words, for example, steam which originates from the nickel precursor and comprises at least nickel and / or steam which originates from the cobalt precursor and thus comprises at least cobalt, is introduced into the reaction space 20 introduced so that the protective layer is formed from the nickel and / or cobalt. Because of the application of organic metal precursors only a few nanometers of metal film on the substrate 12 , especially on the crack 14 , deposited, this metal film does not interfere with further repair work by soldering and / or welding. On the other hand, the metal film formed, for example, as a thin cobalt and / or nickel layer serves as a very good corrosion layer, the metal film being formed, for example, from nickel and / or from cobalt, in particular from a nickel and / or cobalt alloy. For the deposition of nickel and cobalt on the substrate 12 , in particular on its cleaned surface 16 For example, the following precursors are used: As the nickel precursor, for example:

• Bis (N, N'-di-t-butylazetamidinato) nickel (II), (99.99% Ni) puratrem
• As the cobalt precursor, for example, there is used: bis (N, N'-di-i-propylazetamidinato) cobalt (II), min.98%

These metal precursors are metal complexes with amidinate ligands that contain two organic carbon radicals on the amidinate nitrogen atoms and form four-membered chelate ring structures in the coordinated, metallated state. 4 to 6 show the molecular structure of said metal complexes.

Thus shows 4 a basic structure of a bis-amidinate ligand with divalent metal. 5 shows the nickel precursor in its structural formula, and 6 shows the cobalt precursor in its structural formula. In particular shows 4 the monomeric basic structure of the organic metal precursors. In 4 the respective letter R stands for a hydrocarbon radical such as, for example, alkyl, aryl, alkymil, groups which contain no metal atom. The metal amidinates are sufficiently volatile, thermally stable and highly reactive. The high volatility is achieved on the one hand by the outer regions of these metal chelate complexes and on the other hand by the low number of structural units (mostly monomeric) improved. The outer regions are predominantly branched iso-propyl and tertiary-butyl radicals, which, as bulky ligands, prevent interactions of the molecules to form oligomers. The low number of C atoms, the number being for example 1-4, in the short hydrocarbon residues and the associated low molecular weight of these molecules leads to rapid evaporation and high volatility of the metal amidinates. Due to the complex-forming effects of amidinate ligands, the metal amidinates are stable at room temperature, so there is no decomposition before the deposition. 5 shows the coordinated nickel-amidinate complex. The melting point of this nickel complex is 87 degrees Celsius. The corresponding cobalt amidinate complex is in 6 shown. For the cobalt complex, the boiling point at which the sublimation begins is 50 degrees Celsius at 50 mTorr. The melting point is 84 degrees Celsius. Since the metal amidinates are very reactive with oxygen and water vapor, these compounds store in the respective bubblers and are thus protected against environmental conditions such as moisture and oxygen.

Since the decomposition temperature for the nickel and the cobalt amidinate complex is about 300 degrees Celsius, the temperature in the reaction space should be 20 and / or the temperature of the substrate 12 below the decomposition temperature of said precursors, in particular metal precursors.

Add the cobalt and nickel amidinates as a vapor to the substrate 12 and especially on the cleaned crack 14 to direct, the respective, initially liquid metal precursor is vaporized by nebulization in an inert carrier gas such as nitrogen. For this purpose, the solid cobalt and nickel amidinates are dissolved in anhydrous hydrocarbons such as dodecane, tetradecane, toluene, xylene, mesitylene, ethers, esters, or ketones. Thus, for example, the respective vapor having at least one metal is obtained from a liquid solution of an amide ligand metal complex having at least the respective metal, the solution comprising at least one anhydrous hydrocarbon in which the amine complex ligand metal complex is dissolved.

In the respective bubbler, the respective cobalt or nickel amidinate solution is heated above its evaporation temperature to 100 degrees Celsius to 200 degrees Celsius and pneumatically via the line with nitrogen as precursor mist 34 in the reaction space 20 initiated. The metal amidinate molecules chemically become on the substrate 12 , especially on its surface 16 , and thus especially on the surface 16 the crack 14 bound by chemisorption. After complete occupancy of the surface 16 With metal amidinate molecules, sorption stops on the substrate 12 , As a result, for example, a monolayer of cobalt and / or nickel amidinate is produced. After formation of this monolayer, for example, the first step of the deposition process, also referred to as metal deposition, is completed.

For example, in a second step, excess metal amidinate molecules and any volatile reaction byproducts present are removed by means of the suction device 28 , in particular by means of a vacuum pump of the suction device 28 , from the reaction space 20 aspirated and removed by means of a flow of an inert carrier gas. Thus, for example, the reaction space 20 and the substrate 12 flushed with an inert carrier gas or with an inert gas, which also by means of the suction device 28 is sucked, for example. As the inert carrier gas, at least an inert gas such as nitrogen is used.

For example, in the third step, the hydrogen as the second reactant in the reaction space 20 initiated. The hydrogen reacts immediately with the cobalt and / or nickel amidinate to form a pure cobalt and / or nickel film and volatile acetamidine. Fragmentation of the metal amidinates occurs at the metal-nitrogen bond. The metal-nitrogen bond and CN bond in ligands are suitable target break points, with the branched hydrocarbon radicals on the N atom attracting the bonding electrons more strongly than the nickel or cobalt atom and thus a lower binding energy to CO atoms. , Have CH and CC bonds. The decomposition of the metal amidinates is in 7 illustrated.

For example, in the fourth step, the volatile reaction products acetamidine and 2-propane, and excess hydrogen are pumped off or by means of the suction device 28 from the reaction space 20 sucked off, and the reaction space 20 and the substrate 12 are purged with an inert gas such as nitrogen by passing the nitrogen into the reaction space 20 is initiated. Acetamidine and 2-propane are volatile at 200 degrees Celsius to 300 degrees Celsius and can, especially from the reaction space 20 , are completely removed to deposit pure metal films or contaminants such as carbon and nitrogen radicals. The amide derivatives used do not produce any corrosive side effects. In this way, the above-described metal film in the form of the protective layer on the substrate 12 and especially on the crack 14 deposited.

The fifth step, the sixth step, the seventh step and the eighth step combine to form the deposition process, also referred to as the deposition cycle, which can be repeated several times. The metal amidinates and the hydrogen are alternately in the reaction space 20 initiated and in the crack 14 chemisorbed until, for example, the entire surface 16 the crack 14 is completely occupied to the top. Thereafter, no further adsorption takes place. The time between the adsorption of the metal amidinates on the surface 16 the crack 14 and the reaction with hydrogen and cleavage of the ligands and formation of a metal monolayer is on the order of seconds. It is chosen so that in an adequate time the just introduced component with the surface called the crack surface 16 and the excess vapor and any byproducts from a region or space above the substrate 12 be removed. This type of process management limits the surface reactions themselves, so that reproducible metal layers with a calculable composition are deposited. The deposited metal film grows with each subsequent cycle. The number of required process cycles, the reaction time of the coating reactants and the amount of metal amidinates and hydrogen per unit area and cycle depend on the size, in particular depth and / or width, and number of cracks. To avoid oxidation processes, the cobalt and / or nickel coated substrate 12 via a lock, which is filled with inert gas, the repair soldering and / or repair welding supplied.

In 8th is said protective layer, which is also referred to as metal and is formed at least from the metal originating from the steam, with 38 designated. The protective layer 38 is thus a nickel and / or cobalt film, that is a thin layer which comprises at least or exclusively nickel and / or cobalt. Besides, it is off 8th a grain boundary 40 of the substrate 12 recognizable. For example, the aforementioned lock and the storage of the substrate 12 After the etching process and after the deposition process to avoid and thus be able to save, for example, the protective layer 38 occupied with an atomic layer of metal oxide, said atomic layer in 9 recognizable and there with 42 is designated. The atomic situation 42 is also referred to as a film or layer. The protective layer 38 is thus a first layer on the substrate 12 is deposited. The atomic situation 42 is another layer, which on the first layer (protective layer 38 ) and thus on the substrate 12 is deposited.

For the formation of the atomic situation 42 For example, in the eighth step, a reaction of the adsorbed metal amidinates with water vapor is effected or allowed, so that the position 42 is deposited as a metal film with a monolayer of cobalt and / or nickel oxide. The location 42 is thus formed of at least one oxide of the vapor-derived metal, so that the location 42 For example, nickel oxide and / or cobalt oxide. The location 42 is a monolayer of metal oxide, which on the one hand should protect the prefabricated crack surface from further oxidation when the substrate 12 from the device 10 Will get removed. On the other hand, the situation should be 42 so thin that, for example, a subsequent repair process in which repair brazing and repair welding is performed is not disturbed. 10 shows, for example, the reaction equation of the respective metal amidinate with water vapor.

As in the case of the etching process, the respective valves also provide for the deposition process 32a - H for the introduction of the metal precursors and the hydrogen and / or water vapor in the reaction space 20 , At the same time the valves become 32a - H computer-protected changed and controlled, that is, by means of the electronic computing device 36 operated, in particular controlled or regulated. A constant flow of nitrogen as the carrier gas helps to remove the steam, also referred to as reactant gas, in the piping or in the pipeline, for example, to a heated deposition zone. A nickel-cobalt alloy can be achieved by preparing a mixture of the cobalt and nickel precursors. It should be noted that both metal precursors chemically have the same ligand and similar boiling and melting points for the formation of volatile vapors. The substrate coated with nickel and / or cobalt as a result of the deposition process 12 can now be repaired for example by repair brazing and / or repair welding, thereby for example the crack 14 at least partially, in particular at least predominantly or completely close or fill.

The respective, by means of the suction device 28 from the reaction space 20 aspirated fluid can, for example via a valve 44 the suction device 28 a first filter 46 and / or a second filter 48 the suction device 28 be fed, for example, the filter 46 and 48 in a pipe 50 the suction device 28 are arranged. This can be done from the reaction space 20 extracted gas through the pipe 50 stream. In the flow direction of the line 50 flowing fluid is for example the filter 48 downstream of the filter 46 arranged. The filter 48 is designed for example as an activated carbon filter, wherein the filter 46 for example, is designed as a dolomite filter. After the filters 46 and 48 For example, the fluid as so-called exhaust air to an environment 52 the device 10 dismiss.

In particular, it is advantageous if the etching process and / or the deposition process is assisted by an ultrasound effect which acts on the substrate 12 is exercised. First of all, the etching process can be applied to the substrate 12 acting ultrasonic impact are positively influenced. So that the cleaning, reducing gases and metal precursors down to the smallest angle of the surface 16 and thus in the crack 14 reach, it is possible to promote the etching process by an ultrasonic action. Under the ultrasonic action is to be understood that in particular by means of an exciter ultrasonic vibrations of the substrate 12 be effected so that the substrate 12 during the deposition process with ultrasonic vibrations in the reaction space 20 swings. The ultrasonic vibrations can be generated for example by piezo elements and piezoceramics, which, for example, on, in particular, the holding device 24 are installed.

Further, it is possible to increase the reactivity of the HF gas by generating a plasma in the reaction space 20 to increase. The plasma is, for example, with the help of at least one in the reaction space 20 arranged electrode 54 generated, for example, the substrate 12 in particular via the holding device 24 placed on mass M. By applying a voltage, in particular via the electrode 54 For example, at least one or more alternating electrical fields is generated, whereby the plasma is formed or generated. The alternating electric field is generated for example by means of a high-frequency generator RF. In other words, by means of the high-frequency generator RF in particular via the electrode 54 generates a high-frequency electromagnetic field, in particular alternating field, by means of which the plasma is generated. The plasma is generated, in particular, at least or exclusively from the HF gas and / or from a plasma gas which is different from the HF gas and is provided in addition, for example via a plasma gas inlet 56 in the reaction space 20 is initiated. By applying the very high electrical voltage, it ignites a gas discharge, whereby the plasma is formed, for example. About an adjustment device 58 For example, the alternating field or the plasma is controlled and controlled or regulated. The alternating field has, for example, a frequency which lies in the radiofrequency range. In particular, by applying the electrical voltage, the HF gas and / or the plasma gas is ionized, whereby the plasma is formed. The formation of the plasma or the ionization of the HF gas, in particular its HF gas molecules, takes place by means of the electrode 54 instead, which is designed as a so-called shower-head electrode (shower head electrode). The hydrogen and fluoride ions are accelerated by the plasma and thus can adsorb faster at the metal oxide surface. To obtain the conformity of the etching process, the plasma is pulsed. The plasma can drive the reaction of the metal oxides with the HF gas in the direction of metal fluoride formation without the need to use high temperatures.

The reactivity of the hydrogen in the deposition of the metals can be accelerated by the ignition of a gas discharge. The plasma is generated only during the hydrogen phase, if the temperature of the substrate 12 is not sufficient to cleave the ligands.

To remove excess precursors and by-products, for example, getter materials are used as filters, especially as the filters 46 and 48 , used with the pumped fluid and thus with pumped gas molecules from the reaction space 20 enter into a chemical compound or be held by adsorption. For example, dolomite is used to remove excess HF gas. Dolomite consists of calcium and magnesium carbonate and reacts with HF to calcium or magnesium fluoride according to the following equation: $${\text{<figure-callout id="3" label="CaCO" filenames="DE102017223600A1\_0016.png,DE102017223600A1\_0017.png" state="{{state}}">CaCO</figure-callout>}}_3+2\text{HF}={\text{<figure-callout id="2" label="CaF" filenames="DE102017223600A1\_0018.png,DE102017223600A1\_0019.png" state="{{state}}">CaF</figure-callout>}}_2+{\text{<figure-callout id="2" label="H" filenames="DE102017223600A1\_0018.png,DE102017223600A1\_0019.png" state="{{state}}">H</figure-callout>}}_2{\text{<figure-callout id="3" label="CO" filenames="DE102017223600A1\_0016.png,DE102017223600A1\_0017.png" state="{{state}}">CO</figure-callout>}}_{\text{3}}$$

The gaseous metal precursors and organic by-products are absorbed on the surface of activated carbon of, for example, the activated carbon filter.

Overall, it can be seen that the substrate 12 by means of the device 10 and can be cleaned particularly advantageously by means of the method and prepared for subsequent repair operations, without the substrate 12 to heat excessively. In other words, an excessively high temperature load on the substrate 12 be avoided because, for example, the etching proceeds at 300 degrees Celsius to 600 degrees Celsius. For a FIC cleaning, the substrate would have to be removed to remove metal fluorides 12 be heated to over 1600 degrees Celsius. This is due to very high sublimation and boiling temperatures, for example AlF3 a sublimation temperature of 1260 degrees Celsius, CrF3 a melting temperature of more than 1000 degrees Celsius, ZrF3 a melting temperature of 900 degrees Celsius, MiF2 a boiling point of 1750 degrees Celsius and CoF2 a boiling point of 1400 degrees Celsius. For the mentioned fluorides to go into the gaseous state, the substrate would have to 12 be heated to over 1600 degrees Celsius. These temperatures do not withstand the usual materials of gas turbine components. However, at lower temperatures, the above-mentioned fluorides remain on the crack surface. By means of the device 10 however, the metal fluorides, which are difficult to evaporate, are chemically removed at low temperatures. Due to the layered removal of metal oxides, the crack 14 with a high aspect ratio and conforming to the tips cleaned. The material under the metal oxide is not attacked. In addition, a fluoride load on the device 10 and the substrate 12 be kept particularly low. In addition, chemical contaminants and other residues that may interfere with repair welding and / or repair soldering can be avoided.

• - kontrollierter und steuerbarer Einsatz von Chemikalien, damit geringerer Einsatz von umweltbelastenden Chemikalien wie beispielsweise Fluorwasserstoff
• - überschüssiger Fluorwasserstoff wird chemisch mittels wenigstens eines Filters gebunden und gelangt nicht an die Umwelt
• - hochreine, konform gut benetzbare Rissoberfläche bis in die Spitzen für eine strukturelle Konstruktionsreparatur mit Löt- oder Schweißmaterial
• - Digitalisierung des Reinigungs- und Beschichtungsprozesses durch rechnergestützte Steuerung und Kontrolle der Präkursor-Einsatzmengen und -verbrauchsmengen über die Ventile 32a-h und Sensoren möglich.

The etching of the metal oxides and the deposition of the metal layer take place in partial steps. Excess reactants and by-products are removed by suction after each reaction step, and the substrate to be treated 12 as well as the device 10 even with supply lines are flushed with inert gas. In particular, it is possible to produce a clean, highly pinhole-free, highly conformable and thin cobalt, nickel or nickel-cobalt layer for soldering or welding with very good step coverage. Another advantage is that impurities are avoided as the substrate 12 the reaction space 20 does not leave. The cleaning and coating are in the same reaction space 20 performed in succession. In addition, the following effects can be realized:

• - Controlled and controllable use of chemicals, so less use of polluting chemicals such as hydrogen fluoride
• - Excess hydrogen fluoride is chemically bound by means of at least one filter and does not reach the environment
• - Highly clean, conformable, well wettable crack surface right down to the tips for a structural design repair with soldering or welding material
• - Digitization of the cleaning and coating process by computer-aided control and control of the precursor input quantities and consumption quantities via the valves 32a - H and sensors possible.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2011/057829 A1 [0002]
• WO 2010/051174 A1 [0003]

Claims (15)

Method for cleaning at least one substrate (12) having at least one material damage (14), in which the substrate (12) is arranged in a reaction space (20) and cleaned in the reaction space (20), characterized in that: 12) in the reaction space (20) is subjected to at least one etching process for cleaning the substrate (12), wherein the etching process comprises at least the following steps: a) introducing gaseous hydrogen fluoride and water vapor into the reaction space (20); b) after step a): aspirating a fluid comprising at least one gas from the reaction space (20); c) after step b): introducing gaseous trimethylaluminum into the reaction space (20); and d) after step c): aspirating a fluid comprising at least one gas from the reaction space (20) and purging the reaction space (20) and the substrate (12) with an inert gas; and - subjecting the substrate (12) in the reaction space (20) to at least one deposition process after the etching process, the deposition process comprising at least the following steps: e) introducing at least one metal-containing vapor into the reaction space (20); f) after step e): aspirating a fluid comprising at least one gas from the reaction space (20); g) after step f): introducing hydrogen into the reaction space (20); and h) after step g): aspirating a fluid comprising at least one gas from the reaction space (20) and purging the substrate (12) with an inert gas. Method according to Claim 1 , characterized in that at step e) the vapor comprises at least nickel and / or cobalt as the metal. Method according to Claim 1 or 2 , characterized in that in step e) the vapor is obtained from a liquid solution of at least the metal having metal complex with aminidate ligands. Method according to Claim 3 , characterized in that the solution comprises at least one anhydrous hydrocarbon in which the metal complex is dissolved with Aminidat ligands. Method according to Claim 3 or 4 characterized in that the vapor is recovered from the liquid solution such that the solution is heated to or above its vaporization temperature, resulting in the vapor which is introduced into the reaction space together with at least one inert gas at step e). Method according to one of the preceding claims, characterized in that in step a), the gaseous hydrogen fluoride from a hydrogen fluoride-pyridine complex having starting material is obtained. Method according to Claim 6 , characterized in that the gaseous hydrogen fluoride is recovered from the starting material in such a way that the starting material received in a container is heated in such a way that the starting material splits off the gaseous hydrogen fluoride from pyridine. Method according to one of the preceding claims, characterized in that in step a) the gaseous hydrogen fluoride is introduced with at least one inert gas into the reaction space (20). Method according to one of the preceding claims, characterized in that in step a) the reaction space (20) and the substrate (12) are heated to a predeterminable temperature. Method according to Claim 9 , characterized in that the temperature is in a range of including 300 degrees Celsius up to and including 400 degrees Celsius. Method according to one of the preceding claims, characterized in that during the deposition process, a layer (38) comprising at least the metal from the vapor is deposited on the substrate (12). Method according to Claim 11 , characterized in that on the layer (38) at least one at least one metal oxide further layer (42) is deposited by causing a reaction of the steam-derived metal with water vapor, so that the metal oxide of the further layer (42) of the formed from the vapor-derived metal. Method according to one of the preceding claims, characterized in that at least during a part of the etching process and / or at least during a part of the deposition process ultrasonic vibrations of the substrate (12) are effected, so that the substrate (129 performs at least during the part of the induced ultrasonic vibrations. Method according to one of the preceding claims, characterized in that in step a) in the reaction space (20) from the gaseous hydrogen fluoride by applying an electrical voltage, a plasma is formed. Device (10) for cleaning at least one substrate (12) having at least one material damage (14), with a reaction space (20) in which the substrate (12) can be arranged and cleaned, characterized in that: - the device (10 ) at least one supply and introduction means (26) adapted to: o provide gaseous hydrogen fluoride and water vapor and introduce it into the reaction space (20) o to provide gaseous trimethylaluminum and to introduce it into the reaction space (20); o one at least one metal and to provide hydrogen and introduce it into the reaction space (20), and o to provide at least one inert gas and introduce it into the reaction space (20), thereby forming the reaction space (20) and the substrate (12) to flush with the inert gas, and - the device (10) has a suction device (28), which in addition ebildet is to suck a at least one gas comprehensive fluid from the reaction space (20).

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