Method and device for selectively modifying the layer morphology in superconductors

Abstract

The invention relates to a method for local phase transition and structuring of thin films made of superconducting materials, the method comprising the following steps: depositing a thin film (1) made of a superconducting material in a ceramic or insulating phase on a carrier substrate (2) in a deposition system (3); locally applying heat to the thin film (1), wherein regions of the thin film (1) are heated and undergo a phase transition into a superconducting phase (8) so that regions of the superconducting phase (8) form structures that are embedded in the insulating phase.

Description

[0001] Method and device for selective modification of layer morphology in superconductors

[0002] The invention relates to a method and a device for the selective modification of the layer morphology in superconductors by phase transformation and structuring by applying a local heat input.

[0003] Superconductors, especially high-temperature superconductors (HTSC) such as yttrium barium copper oxide (YBCO) and other cuprate-based or iron-based superconductors, are finding increasingly broad applications, for example, in quantum technology, cryoelectronics, power electronics, and telecommunications. However, to make superconductors usable in these areas, micro-fabrication of superconducting structures is necessary. Until now, such fabrication has required complex processes.First, a layer of the superconducting material is applied to a carrier substrate using a common thin-film coating process, such as physical vapor deposition (PVD), molecular beam epitaxy (MBE), pulsed laser deposition (PLD), electrochemical deposition (ECD), reactive evaporation (RE), or chemical vapor deposition (CVD). This is followed by heat treatment at high temperatures to convert the material into a superconducting phase. Structuring can only take place afterward. However, since HTS in particular are composites of several elements with highly anisotropic crystalline structures, etching processes for producing precisely defined structures are often difficult.Reactive ion etching (RIE) or ion beam etching (IBE) are typically used for structuring. However, these complex processes lead to rapid degradation of the layers and are therefore limited to a layer thickness of 50 nm to 100 nm. Alternatively, wet-chemical structuring methods and pulsed laser ablation (PLA) are used to create structures, although both methods have a number of disadvantages. For example, wet-chemical processes lead to a deterioration of the superconducting properties due to chemical degradation of the surfaces. Laser ablation, on the other hand, can cause material damage in the area of ​​the structure edges, with the width of the damaged zone depending on the layer thickness, the laser radiation used, and the number and duration of the laser pulses.Since the laser pulses cause heating of the material, laser ablation can also lead to a loss of oxygen in the material and therefore to a deterioration of the superconducting properties.

[0004] The object of the present patent application is therefore to solve the problems mentioned and to propose a method and a device for the local phase transformation and structuring of thin films of superconducting materials, with which superconducting structures can be produced in a simple, reliable and easily scalable manner.

[0005] This object is achieved by a method according to independent claim 1 and by a device according to claim 18.

[0006] A method for the local phase transformation and structuring of thin films of superconducting materials comprises in particular the following steps:

[0007] Deposition of a thin film of a superconducting material in a ceramic or insulating phase on a carrier substrate in a deposition system, local heat input into the thin film, whereby regions of the thin film are heated and undergo a phase transformation into a superconducting phase, so that regions of the superconducting phase form embedded structures in the insulating phase.

[0008] The process can be used for a variety of common superconductor materials, such as high-temperature superconductors from the group of cuprate-based superconductors, such as YBCO, REBaCuO, or BiSCCO, or iron-based superconductors, such as iron pnictides or iron selenides, to obtain high-temperature superconductor structures. It can also be applied to other metallic superconductors, A15 phases, and amorphous or crystalline alloys to achieve changes in their layer morphology. In the following, the superconducting material is referred to as a thin film.

[0009] All deposition and coating processes commonly used in thin-film technology, such as physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), pulsed laser deposition (PLD), electrochemical deposition (ECD), or even printing processes, can be used to deposit the thin film of superconducting material. The deposition system is a device designed for the corresponding method. The thin film is deposited in an oxygen atmosphere. Different atmospheric conditions, such as gas composition, gas pressure, and temperature, can promote defined layer growth. The carrier substrate can be semiconductor materials, ceramics, glasses, metals, diamonds, or even polymers. The substrate temperature also influences the layer formation.Typically, a substrate temperature of over 500 °C is used for the deposition of HTSC materials, while temperatures around 400 °C are used for iron-based superconductors. After deposition, the superconducting material is present in a ceramic or insulating phase on the carrier substrate.

[0010] The local heat input serves to selectively modify the layer morphology and thus simultaneously fulfills the tasks of the heat treatment and structuring process steps in the conventional manufacturing process chain for superconductor structures. The local heat input can be carried out simultaneously for several structures or groups of structures in a single process step and thus offers particular advantages over writing processes such as laser ablation. The local heat input can take place after deposition or during the deposition of the thin film. Likewise, the local heat input can take place in the deposition system, referred to below as in-situ, or outside the deposition system, referred to below as ex-situ. The local heat input heats areas of the thin film sufficiently so that a phase transformation from the ceramic / insulating phase to the superconducting phase takes place in these areas.Since this transformation occurs only in certain regions, structures are simultaneously formed in the superconducting phase that are embedded in the surrounding parent phase. By controlling the local heat input, the desired geometries of the superconducting structures can be achieved. A material composite of superconducting and non-superconducting regions is created without additional layer removal or deposition. An additional process step for structuring is thus eliminated.

[0011] Local heat input can occur in conjunction with heating of the carrier substrate. Especially during thin-film deposition, an elevated substrate temperature is usually necessary. Local heat input can therefore also be used to heat the carrier substrate or supplement an existing substrate heater. In the latter case, local heat input can serve to significantly increase the thermal energy provided by the substrate heater locally and selectively, so that the temperature required for a phase transition is reached in certain areas of the thin film.

[0012] Local heat input can be achieved directly by induction heating of the thin film. Eddy currents are induced directly into areas of the thin film by at least one induction coil, heating the material through its internal resistance. The geometry of the induction coil determines the geometry of the heated areas and thus also of the resulting structures. The induction coil can, for example, be integrated into a substrate holder of the deposition system, the so-called chuck. Alternatively, the induction coil can also be arranged externally, for example, above the surface of the thin film.

[0013] Induction heating can be achieved by an induction coil integrated into the carrier substrate of the thin film. The induction coil is embedded in a layer of electrically insulating material arranged on the carrier substrate. In this case, the carrier substrate can form a layer stack comprising layers of insulating material with an integrated induction coil, onto which the thin film is then deposited. Because the induction coil is provided on the carrier substrate, its properties can be individually predetermined for each desired structure.

[0014] Instead of heating the thin film directly by induction, the local heat input can also occur indirectly via heat conduction from a trigger material. The trigger material is arranged on the carrier substrate of the thin film. In this case, the carrier substrate can form a layer stack comprising layers of insulating material with embedded trigger material and a possibly integrated induction coil, onto which the thin film is then deposited. The trigger material can be arranged in any desired geometry. Induction coils, for example in the substrate holder or also in the carrier substrate, induce eddy currents in the trigger material, which heats it. The thermal conductivity of the trigger material also heats the thin film in certain areas. In addition to electrical conductivity, the trigger material should therefore also exhibit good thermal conductivity.Materials such as copper, silver, or especially titanium, which also has a high melting temperature, are particularly suitable. The geometry of the trigger material on the carrier substrate thus also determines the geometry of the superconducting structures to be created. The use of a trigger material thus provides greater flexibility in the production of the structures, since a change in the desired structure geometry does not necessarily require a change in the geometry of the induction coil.

[0015] Alternatively, local heat input can also be achieved indirectly through resistance heating by resistive heating elements. The resistive heating elements can be integrated into the carrier substrate of the thin film and electrically contacted to heat the thin film in specific areas through thermal conduction. The resistive heating elements can be arranged in an electrically insulating layer on the carrier substrate. The geometry of the resistive heating elements can determine the geometry of the structures to be created.

[0016] Local heat input using one of the methods described above can be carried out in-situ in the deposition system under an oxygen atmosphere. This eliminates the need for an additional heating device, as used in conventional heat treatments, and process complexity can be reduced. The deposition system can be adapted accordingly to enable local heat input, for example, with induction coils or additional contacts for connecting resistive heating elements. Preferably, local heat input can already occur in-situ during the deposition of the thin film. The resulting thin film is heated locally more than the substrate during deposition, so that the superconducting material undergoes a phase transformation into the superconducting phase in some areas. In this way, the process time for producing superconducting structures can be further reduced.Alternatively, local heat input can also be performed ex-situ in an additional heating chamber under an oxygen atmosphere. While using an additional heating chamber for local heat input spatially separates the deposition and local heat input process steps, it opens up more possibilities for local heat input, for example, by heating the thin film surface.

[0017] Local heat input can also occur during deposition in the deposition system and be completed by further ex-situ heat treatment in a heating chamber. For this purpose, the thin film is locally heated during deposition to stimulate the phase transformation into the superconducting phase in certain areas. Subsequent heat treatment in the heating chamber then selectively converts these areas completely into the superconducting phase, while the surrounding areas remain in the ceramic phase.

[0018] The thin film can, in particular, be a high-temperature superconductor layer. Since known HTSC materials, such as YBCO, REBaCuO, BiSCCO, or iron-based high-temperature superconductors, are difficult to structure using conventional methods, or experience reduced performance due to conventional structuring processes, the process according to the invention is particularly suitable for producing superconducting structures or geometries for these materials.

[0019] The thin film can also be made of other metallic superconductors, Al15 phases, and amorphous or crystalline alloys. Combining heat treatment and structuring can also be advantageous for these materials. At the same time, the process according to the invention can also achieve other improved properties, such as increased ductility.

[0020] Common processes such as PVD, CVD, ALD, PLD, or ECD can be used to deposit the thin film. The thin film can also be produced using printing processes. This makes the process extremely flexible with regard to the thin film deposition method and, therefore, also with regard to the superconducting material to be processed. Furthermore, these conventional methods can be used for the process according to the invention without significant additional processing effort.

[0021] In this context, a thin film can be considered a layer with a thickness of less than 100 pm. Layers of this size are relevant for microtechnology applications. At the same time, the method according to the invention enables the reliable modification of the layer morphology of such layers.

[0022] The described method also offers great flexibility with regard to the carrier substrates used. For example, the carrier substrate can be pre-structured three-dimensionally to achieve additional effects or enable later application. While such pre-structuring of the substrate would complicate structuring of the superconducting material using many conventional methods, it has no negative impact on the selective modification achieved by the method according to the invention. Furthermore, this method can be used to process carrier substrates and thus thin films of superconducting materials to chip, wafer, or even panel size, since the methods for local heat input can be easily scaled to larger areas.

[0023] Through local heat input, temperatures between 200 °C and 2000 °C can be achieved in the thin film. In this way, phase transitions into the superconducting phase can be achieved in thin films made of relevant superconducting materials. Thus, the method according to the invention enables the production of superconducting structures from a variety of superconductors.

[0024] A device for the local phase transformation and structuring of thin films of superconducting materials comprises a deposition system for depositing a thin film of a superconducting material in a ceramic or insulating phase on a carrier substrate, and a device for the local heat input into the thin film, wherein regions of the thin film are heated and undergo a phase transformation into a superconducting phase, so that regions of the superconducting phase form structures embedded in the insulating phase.

[0025] The deposition system can utilize coating processes commonly used in thin-film technology to deposit a thin film of superconducting material in a ceramic or insulating phase. Different atmospheric conditions, such as gas composition, gas pressure, and temperature, can promote defined layer growth. After deposition, the superconducting material is present in a ceramic or insulating phase on the carrier substrate.

[0026] The local heat input device selectively modifies the layer morphology. It thus simultaneously performs the heat treatment and structuring steps of the conventional manufacturing process chain for superconductor structures. The local heat input device can be part of the deposition system, so that local heat input occurs in situ, or it can be provided externally as a standalone device, so that local heat input occurs ex situ.

[0027] The device for local heat input can be configured to also heat the carrier substrate, for example to promote the deposition process of the thin film.

[0028] The device for local heat input can comprise at least one induction coil. This can be arranged in a substrate holder. Eddy currents are induced directly into regions of the thin film by at least one induction coil, which heats the material through its internal resistance. The geometry of the induction coil determines the geometry of the heated regions and thus also of the resulting structures. Alternatively, the induction coil can also be arranged externally, for example, above the surface of the thin film.

[0029] The induction coil can be integrated into the carrier substrate of the thin film. For this purpose, the induction coil can be embedded in a layer of electrically insulating material arranged on the carrier substrate. Since the induction coil is provided on the carrier substrate, its properties can be individually predetermined for each desired structure.

[0030] The carrier substrate can comprise a trigger material that is heated by induction heating. The trigger material can be embedded in an electrically insulating layer. The trigger material can be arranged in any desired geometry. The induction coil in turn induces eddy currents in the trigger material, causing it to heat up. The thermal conductivity of the trigger material also heats the thin film in certain areas. In addition to electrical conductivity, the trigger material should therefore also exhibit good thermal conductivity and a high melting temperature. Materials such as copper, silver, or titanium are therefore particularly suitable. The geometry of the trigger material on the carrier substrate thus also determines the geometry of the superconducting structures to be created.The use of a trigger material thus results in greater flexibility in the production of the structures, since the geometry of the induction coil does not necessarily have to be adjusted when the desired structure geometry is changed.

[0031] Alternatively, the device for local heat input can comprise resistive heating elements. The resistive heating elements can be integrated into the carrier substrate of the thin film and electrically contacted to heat the thin film in certain areas through thermal conduction. The resistive heating elements can be arranged in an electrically insulating layer on the carrier substrate. The geometry of the resistive heating elements can determine the geometry of the structures to be created.

[0032] The device for local heat input can be designed as part of the deposition system. The deposition system can be adapted accordingly to enable local heat input, for example, with induction coils or additional contacts for connecting resistive heating elements. Preferably, the device for local heat input can be configured to perform the local heat input during the deposition of the thin film. The resulting thin film is heated locally more than the substrate during deposition, so that the superconducting material undergoes a phase transformation into the superconducting phase in some areas. In this way, the process time for producing superconducting structures can be further reduced.

[0033] Alternatively, the device for local heat input can also be provided as an external heating chamber. The heating chamber can be a heating chamber such as those used for conventional heat treatments, adapted for the previously described local heat input methods and equipped, for example, with induction coils or additional contacts for connecting resistive heating elements. However, the heating chamber can also be an arrangement tailored to the specific local heat input methods.

[0034] The device for local heat input can also be configured to carry out the local heat input in-situ during the deposition in the deposition system and subsequently carry out a further heat treatment ex-situ.

[0035] The deposition system can be configured to deposit a high-temperature superconductor layer. Since known HTSC materials, such as YBCO, RE-BaCuO, BiSCCO, or iron-based high-temperature superconductors, are difficult to structure using conventional methods, or experience reduced performance due to conventional structuring processes, the device according to the invention is particularly suitable for producing superconducting structures using these materials.

[0036] However, the deposition system can also be configured to deposit other metallic superconductors, Al5 phases, and amorphous or crystalline alloys. The device according to the invention also simplifies the production of superconducting structures for these processes.

[0037] The deposition system can use a common process such as PVD, CVD, ALD, PLD, or ECD to deposit the thin film. The deposition system can also be configured to produce the thin film using a printing process.

[0038] In this context, a thin film can be considered a layer with a thickness of less than 100 μm. The device described enables selective modification of the layer morphology of such layers.

[0039] The deposition system can be configured to deposit thin films onto three-dimensionally pre-structured carrier substrates. The device according to the invention thus facilitates the production of three-dimensional structures from superconducting materials. The deposition system and the device for local heat input can also be configured to provide carrier substrates of chip, wafer, or panel size with superconducting structures. Thus, large-area superconducting structures can be produced using the described device for local phase transformation and structuring of thin films made of superconducting materials.

[0040] The local heat input device can be configured to achieve temperatures between 200 °C and 2000 °C in the thin film and can therefore initiate a phase transition into the superconducting phase in a variety of relevant superconducting materials.

[0041] The method and device according to the invention thus solve a multitude of problems that arise in the microtechnical production of superconducting structures. A material composite consisting of a superconducting phase and an insulating phase can be easily produced from a thin film, so that the superconducting structures are electrically insulated from each other. Since no subsequent structuring by etching or laser ablation is required, the structures do not suffer any damage that could impair their performance. Manufacturing can be performed in situ to further reduce process times and equipment costs.

[0042] The described embodiments of the method and device for local phase transformation and structuring of thin films of superconducting materials can be used individually or combined to achieve additional effects and to simplify the production of structures of superconducting materials and to enable them for a variety of materials and applications.

[0043] The above-mentioned and further aspects of the invention will become apparent from the detailed description of the embodiments given with the aid of the following figures, of which:

[0044] Fig. 1 schematically shows an embodiment of the method according to the invention,

[0045] Fig. 2 schematically shows a further embodiment of the method according to the invention,

[0046] Fig. 3 schematically shows another embodiment of the method according to the invention,

[0047] Fig. 4 schematically shows another embodiment of the method according to the invention,

[0048] Fig. 5 schematically shows another embodiment of the method according to the invention,

[0049] Fig. 6 schematically shows another embodiment of the method according to the invention,

[0050] Fig. 7 schematically shows another embodiment of the method according to the invention,

[0051] Fig. 8 schematically shows another embodiment of the method according to the invention,

[0052] Fig. 9 schematically illustrates a further embodiment of the method according to the invention, and Fig. 10 schematically illustrates a further embodiment of the method according to the invention.

[0053] The claimed method will be explained in more detail below based on the accompanying drawings. Like reference numerals refer to like elements.

[0054] Figs. 1 to 5 schematically illustrate methods according to the invention and the devices used, in which the local heat input occurs in-situ with the deposition system 3. Figs. 6 to 10, however, illustrate methods according to the invention and the devices used, in which the local heat input occurs ex-situ with a heating chamber 12.

[0055] The figures each show the step of local heat input into the thin film 1 as well as the resulting structures in the superconducting phase 8. The thin film 1 in the ceramic or insulating phase of the superconducting material is previously deposited onto the carrier substrate 2 by a deposition system 3 in a process step not shown. The deposition can be carried out using a common coating process in thin-film technology such as PVD, CVD, ALD, PLD, or ECD. The thin film 1 can also be produced using a printing process.

[0056] The carrier substrate 2 is a chip, a wafer, or a panel made of semiconductor material, ceramic, glass, metal, diamond, or even polymer. The material of the carrier substrate is selected based on the intended use and the superconducting material used. The carrier substrate 2 can be heated during the deposition process by the device for local heat input.

[0057] The thin film 1 consists of a superconducting material. It can be a high-temperature superconductor from the group of cuprate-based superconductors, such as YBCO, REBaCuO, or BiSCCO, or an iron-based superconductor, such as iron pnictides or iron selenides. It can also be a superconducting material from the group of amorphous or crystalline alloys, metallic superconductors, or Al5 phases. Fig. 1 schematically shows the local heat input into the thin film 1 by direct induction heating in-situ in the deposition system 3. The local heat input takes place in an oxygen atmosphere 4. The induction heating is achieved by an induction coil 6 arranged in the substrate holder 5. The induction coil 6 generates an electromagnetic field 7 that induces eddy currents directly in the thin film 1. The thin film 1 is locally heated due to the resistance of the layer material.The arrangement of the induction coil 6 determines the geometry of the heated regions. Sufficient heating, between 200 °C and 2000 °C depending on the superconducting material used, causes a phase transformation from the ceramic or insulating phase of the superconducting material to the superconducting phase 8 in the regions affected by the local heat input. This results in structures in the thin film 1 consisting of the superconducting phase 8 that are embedded in the non-converted phase and thus insulated from one another.

[0058] Fig. 2 schematically shows another embodiment of local heat input by means of direct induction heating into the thin film 1 in-situ in the deposition system 3. The local heat input takes place in an oxygen atmosphere 4. The induction heating is carried out by means of an induction coil 6 arranged in the layer stack of the carrier substrate 2. This is embedded in an insulating layer 9. The induction coil 6 generates an electromagnetic field 7 that induces eddy currents directly in the thin film 1. The resistance of the layer material heats the thin film 1 locally. The arrangement of the induction coil 6 determines the geometry of the heated regions. Since in this embodiment the induction coil 6 is integrated into the carrier substrate 2, the entire substrate holder 5 does not have to be adapted to change the desired geometry of the structures to be created.Instead, a separate carrier substrate 2 can be produced for each desired geometry.

[0059] Fig. 3 schematically shows the indirect local heat input by means of induction heating into a trigger material 10 and heat conduction into the thin film 1. The local heat input takes place in an oxygen atmosphere 4. The induction heating is carried out by means of an induction coil 6 integrated into the substrate holder 5. The induction coil 6 generates an electromagnetic field 7 that induces eddy currents in the trigger material 10. This is embedded in an electrically insulating layer 9 of the carrier substrate 2. The latter is heated by the resistance of the trigger material 10. The local heating of the thin film 1 occurs through heat conduction from the trigger material 10 into the thin film 1. The arrangement of the trigger material on the carrier substrate determines the geometry of the heated regions.In this embodiment, the induction coil 6 is firmly integrated into the substrate holder 5, but the geometry of the superconducting phase 8 is predetermined by the geometry of the trigger material 10 on the carrier substrate 2, so that if the desired geometry is changed, only the carrier substrate 2 needs to be changed.

[0060] The embodiment of Fig. 4 is similar to the embodiment shown in Fig. 3, but here both the induction coil 6 and the trigger material 10 are integrated into the layer stack of the carrier substrate 2. These are embedded in insulating layers 9, which could be two separate layers or a single continuous layer. In this embodiment, the structures in the superconducting phase 8 are completely independent of the substrate holder 5.

[0061] Fig. 5 schematically illustrates the indirect local heat input by means of resistance heating of resistive heating elements 11. The local heat input takes place in an oxygen atmosphere 4. Heating is achieved by means of resistive heating elements 11 integrated into the layer stack of the carrier substrate 2. These are embedded in an electrically insulating layer 9. Due to the resistance of the resistive heating elements, they heat up under current flow. The local heating of the thin film 1 occurs through thermal conduction of the heating elements 11. The arrangement of the resistive heating elements 11 determines the geometry of the heated regions and thus also the geometry of the structures created in the superconducting phase 8.

[0062] The embodiments shown in Fig. 1 to Fig. 5 have in common that the local heat input takes place in-situ in the deposition system 3. This enables the local heat input to take place simultaneously with the deposition of the thin film 1. In Fig. 6, on the other hand, the local heat input by means of direct induction heating into the thin film 1 ex-situ in the heating chamber 12 is shown schematically. The process otherwise corresponds to the embodiment shown in Fig. 1: The local heat input takes place in an oxygen atmosphere 4. The induction heating is carried out by means of an induction coil 6 arranged in the substrate holder 5. The induction coil 6 generates an electromagnetic field 7 which induces eddy currents directly in the thin film 1. The thin film 1 is heated locally due to the resistance of the layer material. The arrangement of the induction coil 6 determines the geometry of the heated regions.Through sufficient heating, depending on the superconducting material used, between 200 °C and 2000 °C, a phase transformation from the ceramic or insulating phase of the superconducting material into the superconducting phase 8 occurs in the areas affected by the local heat input. This results in structures in the thin film 1 consisting of the superconducting phase 8 that are embedded in the non-converted phase and thus insulated from each other.

[0063] Fig. 7 schematically shows another embodiment of local heat input by means of direct induction heating into the thin film 1 ex-situ in the heating chamber 12. The local heat input takes place in an oxygen atmosphere 4. The induction heating is carried out by means of an induction coil 6 arranged in the layer stack of the carrier substrate 2. This is embedded in an insulating layer 9. The induction coil 6 generates an electromagnetic field 7 that induces eddy currents directly in the thin film 1. The resistance of the layer material heats the thin film 1 locally. The arrangement of the induction coil 6 determines the geometry of the heated regions. Since in this embodiment the induction coil 6 is integrated into the carrier substrate 2, the entire substrate holder 5 does not have to be adapted to change the desired geometry of the structures to be produced.Instead, a separate carrier substrate 2 can be produced for each desired geometry.

[0064] Fig. 8 schematically illustrates the indirect local heat input by means of induction heating into a trigger material 10 and heat conduction into the thin film 1 ex-situ in the heating chamber 12. The local heat input takes place in an oxygen atmosphere 4. The induction heating is carried out by means of an induction coil 6 integrated into the substrate holder 5. The induction coil 6 generates an electromagnetic field 7 that induces eddy currents in the trigger material 10. This is embedded in an electrically insulating layer 9 of the carrier substrate 2. The latter is heated by the resistance of the trigger material 10. The local heating of the thin film 1 occurs through the heat conduction of the trigger material 10. The arrangement of the trigger material on the carrier substrate determines the geometry of the heated regions.In this embodiment, the induction coil 6 is firmly integrated into the substrate holder 5, but the geometry of the superconducting phase 8 is predetermined by the geometry of the trigger material 10 on the carrier substrate 2, so that if the desired geometry is changed, only the carrier substrate 2 needs to be changed.

[0065] The embodiment of Fig. 9 again corresponds to the embodiment shown in Fig. 8, but here both the induction coil 6 and the trigger material 10 are integrated into the layer stack of the carrier substrate 2. These are embedded in insulating layers 9, which could be two separate layers or a single continuous layer. In this embodiment, the structures in the superconducting phase 8 are completely independent of the substrate holder 5.

[0066] Fig. 10 schematically illustrates the indirect local heat input by means of resistance heating of resistive heating elements 11 ex-situ in the heating chamber 12. The local heat input takes place in an oxygen atmosphere 4. Heating is achieved by means of resistive heating elements 11 integrated into the layer stack of the carrier substrate 2. These are embedded in an electrically insulating layer 9. Due to the resistance of the resistive heating elements, they heat up under current. The local heating of the thin film 1 occurs through thermal conduction of the heating elements 11. The arrangement of the resistive heating elements 11 determines the geometry of the heated regions and thus also the geometry of the structures produced in the superconducting phase 8.Although the use of an external heating chamber 12 requires an additional process step and the transfer of the carrier substrate 2 from the deposition system 3 into the heating chamber 12, it can also enable additional options for local heat input. For example, with this approach, the induction coil 6, the trigger material 10, or the resistive heating elements 12 could also be arranged on the surface side, i.e., above the thin film 1 in the illustration of the figures, or even on both sides.

[0067] As can be seen from the above embodiments, the method and device according to the invention for the local phase transformation and structuring of thin films made of superconducting materials enable the production of superconducting structures from a wide variety of superconducting materials. Compared to conventional methods, production requires fewer process steps and reliably delivers superconducting structures with advantageous properties. Due to the good scalability of the local heat input methods used, the method can also be used to structure larger areas, enabling industrial applicability.

[0068] The embodiments shown here are not limiting. In particular, the features of these embodiments can be combined with one another to achieve additional effects. It will be obvious to those skilled in the art that modifications can be made to these embodiments without departing from the fundamental principles of the subject matter of this patent application, the scope of which is defined in the claims.

Claims

Patent claims 1. A method for the local phase transformation and structuring of thin films of superconducting materials, comprising the steps: Deposition of a thin film (1) of a superconducting material in a ceramic or insulating phase on a carrier substrate (2) in a deposition system (3), local heat input into the thin film (1), wherein regions of the thin film (1) are heated and undergo a phase transformation into a superconducting phase (8), so that regions of the superconducting phase (8) form structures embedded in the insulating phase.

2. Method according to claim 1, characterized in that the local heat input takes place together with a heating of the carrier substrate (2).

3. Method according to claim 1 or 2, characterized in that the local heat input is effected by induction heating directly into the thin film (1) by an induction coil (6) arranged in a substrate holder.

4. Method according to claim 1 or 2, characterized in that the local heat input by induction heating takes place directly into the thin film (1) by an induction coil (6) which is integrated in the carrier substrate (2, 9) of the thin film (1).

5. Method according to claim 3 or 4, characterized in that the local heat input is effected by indirect heat conduction into the thin film by means of induction heating into a trigger material (10) on the carrier substrate (2).

6. Method according to claim 1 or 2, characterized in that the local heat input is effected by indirect heat conduction into the thin film (1) by means of resistance heating of resistive heating elements (11) which are arranged in the carrier substrate (2, 9) of the thin film (1).

7. Method according to one of claims 1 to 6, characterized in that the local heat input takes place in-situ in the deposition plant (3) under an oxygen atmosphere (4).

8. Method according to one of claims 1 to 6, characterized in that the local heat input takes place ex-situ in a heating chamber (12) under an oxygen atmosphere (4).

9. Method according to one of claims 1 to 6, characterized in that the local heat input takes place in-situ during the deposition and is subsequently subjected to ex-situ heat treatment.

10. Method according to one of the preceding claims, characterized in that the thin film (1) is an HTSC layer.

11. Method according to one of claims 1 to 9, characterized in that the thin film (1) additionally consists of further metallic superconductors, Al5 phases or an amorphous or crystalline alloy.

12. Method according to one of the preceding claims, characterized in that the deposition of the thin film (1) is carried out by means of PVD, CVD, ALD, PLD, ECD or by printing processes, and / or the thin film (1) has a thickness of less than 100 pm after deposition.

13. Method according to one of the preceding claims, characterized in that the carrier substrate (2) is three-dimensionally pre-structured, and / or the carrier substrate (2) is a chip, a wafer or a panel.

14. Method according to one of the preceding claims, characterized in that a local temperature of 200 °C to 2000 °C is achieved in the thin film (1) by the local heat input.

15. Device for the local phase transformation and structuring of thin films of superconducting materials, comprising a deposition system for depositing a thin film (1) of a superconducting material in a ceramic or insulating phase on a carrier substrate (2), a device for the local heat input (6, 11) into the thin film (1), wherein regions of the thin film (1) are heated and undergo a phase transformation into a superconducting phase (8), so that regions of the superconducting phase (8) form structures embedded in the insulating phase.

16. Device according to claim 15, characterized in that the device for local heat input (6) is configured to also heat the carrier substrate (2).

17. Device according to claim 15 or 16, characterized in that the device (6, 11) for local heat input comprises an induction coil (6) in a substrate holder (5).

18. Device according to claim 15 or 16, characterized in that the device for local heat input (6, 11) comprises an induction coil (6) in the carrier substrate (2, 9).

19. Device according to claim 17 or 18, characterized in that a trigger material (10) is arranged on the carrier substrate (2, 9), which is heated by induction heating.

20. Device according to claim 15 or 16, characterized in that the device for local heat input (6, 11, 12) comprises resistive heating elements (11) in the carrier substrate (2, 9).

21. Device according to one of claims 15 to 20, characterized in that the device for local heat input (6, 11) is part the separation system (3) so that a local heat input can take place in-situ in the separation system (3).

22. Device according to one of claims 15 to 20, characterized in that the device for local heat input (6, 11) is part of an external heating chamber (12), so that a local heat input can take place ex-situ after the deposition of the thin film (1).

23. Device according to one of claims 15 to 20, characterized in that the device for local heat input (6, 11) is configured to carry out the local heat input in-situ during the deposition and to carry out a second heat treatment ex-situ after the deposition.

24. Device according to one of claims 15 to 23, characterized in that the deposition system (3) is configured to deposit a thin film (1) from an HTSL.

25. Device according to one of claims 15 to 23, characterized in that the deposition system (3) is configured to deposit additional thin films (1) of further metallic superconductors, Al5 phases or an amorphous or crystalline alloy.

26. Device according to one of claims 15 to 25, characterized in that the deposition system (3) is configured to deposit a thin film (1) by means of PVD, CVD, ALD, PLD, ECD, or printing processes, and / or the deposition system (3) is configured to deposit a thin film (1) with a thickness of up to 100 pm.

27. Device according to one of claims 15 to 26, characterized in that the deposition system (3) is configured to deposit a thin film (1) onto a three-dimensionally pre-structured carrier substrate (2) and / or the deposition system (3) and the device for local heat input (6, 11) are configured to process carrier substrates (2) in chip, wafer or panel size.

8. Device according to one of claims 15 to 27, characterized in that the device for local heat input (6, 11) is configured to reach temperatures of 200 °C to 2000 °C in the thin film (1)

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