Support substrate for nanostructures

Abstract

A support substrate (1) for nanostructures (2), in particular for carbon nanotubes, is provided, the support substrate (1) comprising a plurality of cantilever pairs (13), between each cantilever pair adapted to hold a nanostructure (13). At least some of the plurality of cantilever pairs (13) are configured along at least a curved portion or an angled portion of the periphery (11) of the support substrate (1) such that the at least some of the cantilever pairs extend in different, non-parallel directions. Furthermore, an apparatus (4) for attaching a nanostructure (2) to a device substrate (3) by means of such a support substrate (1) and a method for attaching a nanostructure (2) to a device substrate (3) by means of such a support substrate (1) are provided.

Description

Technical Field

[0001] The present invention relates to a support substrate for nanostructures, in particular carbon nanotubes. The support substrate is used to support the nanostructure and to attach the nanostructure to a device substrate. The present invention also relates to an apparatus for attaching the nanostructure to a device substrate via such a support substrate and a method for attaching the nanostructure to a device substrate via such a support substrate. Background Art

[0002] Nanostructures are increasingly being used in nanoelectromechanical devices for a variety of applications. Especially with regard to semiconductor devices, nanostructures are expected to play an important role in the future. Transistors and simple electronic circuits have been successfully fabricated using semiconducting and metallic carbon nanotubes.

[0003] A particular challenge in the manufacture of devices with nanostructures is the growth of individual nanostructures separated from each other (rather than bundled nanostructures), and the correct transfer and attachment of the nanostructures from the growth substrate to the target device. In the prior art, random or parallel deposition of, for example, nanotubes on a device substrate with multiple devices is often applied. However, in the case of random deposition, most of the devices need to be discarded because no or too many nanostructures are deposited, or the nanostructures are not correctly positioned on the device. As a result, the yield of devices is quite low when using such random deposition procedures.

[0004] In order to overcome these problems associated with random deposition, the growth of suspended or self-supporting nanostructures, such as carbon nanotubes in the form of cantilevers, has recently been developed: by suspending the nanostructure between a pair of cantilevers, the carbon nanotubes can be engineered away from any device in which the carbon nanotubes will be applied later. In this way, the nanostructure can be produced in an optimal environment and with minimal charge noise originating from, for example, the interface of a semiconductor device. By growing or depositing the suspended nanostructure between horizontal cantilevers, it is also possible to pre-select the nanostructure to be used by optical methods applying laser technology. By such pre-selection, non-destructive optical methods (such as Raman spectroscopy) can be used to ensure the quality of the nanostructure used. The growth substrate can then be brought close to the device substrate so that the pre-selected nanostructure is transferred to the device in which the nanostructure will be used.

[0005] The growth of suspended nanostructures in the form of carbon nanotubes between cantilevers and the subsequent transfer of the nanotubes to nanoelectromechanical devices has been demonstrated, for example, in Cubaynes, LC Contamin, MC Dartiailh, MM Desjardins, A. Cottet, MR, Delbecq, T. Kontos, "Nanoassembly technology of carbon nanotubes for hybrid circuits-QED" (Appl. Phys. Lett. 117 (2020) 114001).

[0006] M. Muoth and C. Hierold's "Transferring Carbon Nanotubes to Microactuators with Low Thermal Budget to Achieve Hysteresis-Free Transistors" (2012 IEEE 25th International Conference on Microelectromechanical Systems (MEMS), IEEE (2012) 1352-1355) discloses assembling carbon nanotube field effect transistors using a growth substrate including a cantilever structure.

[0007] Another prior art document disclosing device fabrication using a nanostructure held between two cantilevers on a growth substrate is V. Ranjan, G. Puebla-Hellmann, M. Jung, T. Hasler, A. Nunnenkamp, ​​M. Muoth, C. Hierold, A. Wallraff, C. Schonenberger, “Clean carbon nanotubes coupled to superconducting impedance matching circuits” (Nature Communications 6 (2015) 7165).

[0008] Another document that discloses growing nanostructures between horizontally extending cantilevers and subsequently transferring them to a device substrate is, for example, S. Blien, P. Steger, A. Albang, N. Paradiso, AK Huttel's "Transfer of Carbon Nanotubes into Quantum Device Geometries Based on Quartz Tuning Forks" (Phys. Status Solidi B. 255 (2018) 1800118).

[0009] The method for growing nanostructure and transferring it to target device in the above-mentioned prior art has the disadvantage of limited scalability. For the industrial production of a large number of identical or similar devices, the methods known in the prior art so far are limited in efficiency, i.e., manufacturing speed. And process control is limited, which inevitably leads to a large number of discarded devices. Therefore, it is not very cost-effective to produce devices with nanostructure according to typical prior art methods. However, it can be expected that, for example, next-generation sensors, computer chips and quantum processors will be used more and more in the future. The ability of industrial large-scale production of such sensors, computer chips and quantum processors comprising nanostructures will be a key factor in the widespread application of this technology to various appliances. Summary of the invention

[0010] It is an object of the present invention to provide a support substrate for producing nanostructures, in particular carbon nanotubes, which allows particularly efficient and therefore cost-effective production of devices having these nanostructures.

[0011] This object is solved by a support substrate as claimed in claim 1. Claim 9 claims an apparatus for attaching a nanostructure to a device substrate via such a support substrate. Claim 14 provides a method for attaching such a nanostructure to a device substrate. Further embodiments are provided in the dependent claims.

[0012] Thus, the present invention provides a support substrate for nanostructures, in particular for carbon nanotubes or graphene, the support substrate comprising a plurality of cantilever pairs, each cantilever pair being adapted to hold the nanostructure between them. At least some of the plurality of cantilever pairs are configured along at least a curved or angled portion of the periphery of the support substrate such that the at least some of the cantilever pairs extend in different, non-parallel directions.

[0013] By having a plurality of cantilever pairs arranged in a manner that the cantilever pairs extend in different, non-parallel directions with at least a curved or angled portion along the periphery of the support substrate, the support substrate can have a significantly greater number of cantilevers, and therefore a significantly greater number of nanostructures held thereon. Furthermore, and even more importantly, the support substrate becomes scalable in terms of its size and the number of cantilever pairs, because if the cantilever pairs extend in different, non-parallel directions, mechanical collisions between the support substrate and adjacent devices can be avoided to a considerable extent. In the prior art, the cantilevers are usually arranged in parallel on one side of a rectangular support substrate, which leads to the problem that the cantilevers will collide with adjacent devices when the nanostructures are transferred to the device. Since the devices are usually evenly spaced in rows adjacent to each other on a device substrate in the form of, for example, a wafer or tray, the cantilevers extending in parallel are prone to collision with adjacent devices if the support substrate is extended to a larger number of cantilever pairs extending all in parallel. Therefore, the usual production process according to the prior art has very limited scalability. In contrast, for the method according to the invention, wherein the cantilever pairs are configured along at least a curved or angled portion of the periphery of the support substrate such that the cantilever pairs extend in different, non-parallel directions, providing a larger support substrate with a larger number of cantilever pairs does not result in collisions, or results in collisions to a much lesser extent. As a result, the production process of devices with nanostructures becomes scalable. As a result, a more efficient and therefore more cost-effective device production can be achieved.

[0014] Thus, since the cantilever pairs are arranged along at least a curved or angled portion of the perimeter of the support substrate, preferably even along the entire perimeter, the number of cantilever pairs can be significantly increased. In a preferred embodiment, the support substrate has more than 1000 cantilever pairs, more preferably more than 3000 cantilever pairs, and most preferably more than 5000 cantilever pairs. In contrast, rectangular support substrates according to the prior art having cantilevers only along one side of the substrate typically include only 50 to 100 cantilever pairs.

[0015] In a preferred embodiment, the support substrate is not only used to support the nanostructure, but also to grow the nanostructure. In this case, the support structure may also be referred to as a growth structure for producing the nanostructure. The growth of the nanostructure between the cantilever pairs of the support substrate can be initiated by providing a suitable catalyst at the corresponding position of the support structure. In other embodiments, the nanostructure is not grown on the support substrate, but is dispersed in a solution, and the nanostructure is transferred or "fished" from the solution to the support substrate by immersing the cantilever pairs of the support structure in the solution. In another embodiment, the nanostructure is not grown on the support structure either, but is deposited on the cantilever pairs, for example, by spraying.

[0016] Nanostructures are considered to be structures of medium size between microscopic and molecular structures. Nanostructures are included in structures within the nanometer (usually 1nm to 100nm) range. Nanostructures can have an elongated shape and be in the form of, for example, nanotubes or nanowires. However, it can also have a two-dimensionally extended shape and be in the form of, for example, graphene variants, transition-metal dichalcogenide layers or boron nitride nanosheets. Nanostructures are preferably suspended or self-supporting nanostructures.

[0017] Nanotubes, in particular carbon nanotubes, have two-dimensional dimensions in the nanometer range, ie the diameter of the tube is between 0.1 nm and 100 nm. However, the length of the nanotube can be much greater.

[0018] The cantilever preferably all extends outward from the periphery of the main part of the supporting substrate. The extension of each cantilever is preferably in the horizontal direction, i.e. perpendicular to the direction of gravity. Therefore, each of the cantilevers preferably has an elongated rod-like or rod-like design, with its free end facing away from the main part of the supporting substrate. Advantageously, each cantilever pair includes two cantilevers extending in parallel. Then one or more nanostructures are usually grown between the two cantilevers in the vertical direction. Therefore, the cantilever pair is not only suitable for keeping the nanostructure between them, but also preferably suitable for growing the nanostructure between them. In other embodiments, the nanostructure grows elsewhere before being deposited on the cantilever pair. Preferably, the nanostructure is attached to the target device by lowering the supporting substrate to the device substrate in a manner that the nanostructure is located on the target position of the device. Therefore, in order to transfer the nanostructure to the target device, the device or at least a portion thereof is preferably positioned between the cantilevers.

[0019] In a particularly preferred embodiment, the plurality of cantilever pairs are distributed along the entire periphery of the support substrate. In the case of a circular support substrate, this means that the portions of the periphery without cantilever pairs each span an arc of less than 90°, preferably less than 60°, more preferably less than 45° and most preferably less than 30°. In the case of a polygonal support substrate, the distribution of the plurality of cantilever pairs along the entire periphery means that each edge formed by the polygonal shape comprises at least one cantilever pair.

[0020] Each of the cantilever pair preferably extends outwardly in an approximately radial direction of the supporting substrate. An approximately radial direction is understood to be a direction which deviates from an exact radial direction preferably by less than 45°, more preferably by less than 20°, most preferably by less than 5°.

[0021] The perimeter of the support substrate preferably has a circular or regular polygonal overall shape. These regular geometric overall shapes of the support substrate are particularly suitable for scalability.

[0022] A plurality of cantilever pairs can be but not necessarily uniformly distributed along the entire periphery of the supporting substrate. On the contrary, they can also be configured into a group of a plurality of cantilever pairs extending in parallel to each other. Then, the distance between the cantilever pairs in each group is usually different, and is preferably an integer multiple smaller than the distance between the two groups. Alternatively or additionally, the groups can also deviate from each other in the direction along which the cantilever pairs extend. Preferably, any two adjacent groups of cantilever pairs extending in parallel to each other are at an angle of no more than 10°, preferably no more than 8°, and more preferably no more than 6° to each other. In each group, the cantilever pairs preferably extend in parallel. However, cantilever pairs of different groups can also extend in different directions. The configuration of the cantilever pairs in groups brings the following advantages: in terms of the transfer of the nanostructure, the supporting substrate can be optimally adapted to the device substrate in which the device is usually evenly spaced apart in rows adjacent to each other.

[0023] In each group, the cantilever pairs are preferably evenly spaced. The groups are preferably evenly distributed, i.e. at regular distances, and advantageously distributed along the entire periphery of the support substrate. The groups can in particular be arranged along a circular periphery formed by the main part of the support substrate. In the region of each group, the support substrate can have a radial extension, which extends radially outwards from the main part of the support substrate. The cantilever then extends outwards from the radial extension. Thus, a radial extension can be associated with each group of a plurality of cantilever pairs.

[0024] Each group of the plurality of cantilever pairs preferably extends outwardly along an approximately radial direction of the support substrate, more preferably along a radial direction. An approximately radial direction is understood as a direction deviating from an exact radial direction by preferably less than 45°, more preferably less than 20°, most preferably less than 5°.

[0025] The support substrate can be, but need not be, integrally made in one piece. Thus, in certain embodiments, the cantilever pair can be made in one piece with the main portion of the support substrate. However, in other embodiments, the cantilever pair, in particular the radially extending portion including the cantilever pair, can be attached to the main portion of the support substrate in such a manner that they are not made in one piece and are, for example, made of a material different from the main portion. For example, the main portion of the support substrate can be in the form of a circular or polygonal plate, to which a plurality of radially extending portions including the cantilever pair are attached along its periphery. In this case, the radially extending portions including the cantilever pair form the support substrate together with the main portion. Therefore, by, for example, attaching a plurality of prior art support substrates having a rectangular shape and having the cantilever pair arranged in parallel only on one side thereof to the periphery of the circular or rectangular plate, the support substrate of the present invention can be provided in a particularly easy manner.

[0026] Preferably, the support substrate has a flat shape as a whole. Thus, the extension of the support substrate in two perpendicular spatial directions is preferably at least two digit times, more preferably at least three digit times, the extension in a third perpendicular spatial direction. The plurality of cantilever pairs preferably extend in a common plane. Thus, preferably, the extensions of all cantilevers are in the same plane, more preferably in the same plane as the main part of the support substrate.

[0027] Preferably, the device substrate has a flat shape as a whole. Thus, the extension of the device substrate in two perpendicular spatial directions is preferably at least two-digit times, more preferably at least three-digit times, the extension in a third perpendicular spatial direction. In each case, the device to which the nanostructure is to be attached is formed by the device substrate. The device substrate may comprise only a single device. However, preferably, it comprises a plurality of devices, in particular nanoelectromechanical devices. Nanoelectromechanical devices are electromechanical devices having functional components with dimensions in the nanometer range. The devices may in particular be semiconductor devices.

[0028] The invention also relates to an apparatus for attaching nanostructures, in particular carbon nanotubes, to a device substrate, the apparatus comprising:

[0029] a holder for holding the support substrate described above, the support substrate comprising a plurality of cantilever pairs extending in different, non-parallel directions in a common plane; and

[0030] A positioner is used to position a device substrate for attachment of one or more nanostructures relative to a support substrate.

[0031] The apparatus is adapted to move the holder and the positioner relative to each other in such a manner that the nanostructures respectively held between the cantilever pairs are brought from the support substrate to a plurality of attachment points on the device substrate for attachment to the device substrate.

[0032] The apparatus is adapted to rotate the support substrate about a rotation axis extending perpendicularly through a common plane of the plurality of cantilever pairs so as to sequentially attach the nanostructures to the device substrate.

[0033] By rotating the support substrate to sequentially place the nanostructures on the device substrate, a particularly simple and efficient manufacturing of the device can be achieved. As further indicated above, the concept of a support substrate having a curved or angled perimeter and having a non-parallel pair of cantilevers is directly linked to the concept of rotating the support substrate to attach the nanostructures to the device substrate. Thus, the support substrate and the device as described above relate to a single inventive concept.

[0034] The device is preferably a motorized device, which means that the holder can be moved relative to the positioner by means of a motor, in particular an electric motor.

[0035] The holder relates to a component of the apparatus that allows the support substrate to be attached to the apparatus in order to transfer the nanostructures from the support substrate to the device substrate. A positioner is used to position the device substrate so that the nanostructures can be safely and accurately transferred from the support substrate to the device substrate. Therefore, a positioner is preferably used to hold the device substrate in a desired position during the transfer.

[0036] In a preferred embodiment, the holder is movable, particularly movable by a motor, and the locator is fixed. However, in other embodiments, it is also conceivable that vice versa is also true, or the holder and the locator are movable.

[0037] In a particularly preferred embodiment, the axis of rotation is tilted or tiltable relative to the geometric normal of the device substrate plane at which the attachment points are arranged. The device substrate plane is thus defined by the arrangement of the attachment points. The attachment points are the points at which the nanostructures are attached to the device substrate. In the case where the nanostructures are carbon nanotubes, there are typically two attachment points for each nanostructure. By tilting the axis of rotation relative to the device substrate to transfer the nanostructures, collisions of the cantilever with adjacent devices can be particularly well avoided, while still ensuring that the nanostructures are very accurately placed on the device substrate.

[0038] The tilt angle at which the axis of rotation is tilted or tiltable relative to the geometric normal to the component substrate plane is preferably in the range of 1° to 40°, more preferably in the range of 4° to 20°, in particular 4° to 10°. Tilt angles within these ranges have proven to be particularly well suited for avoiding collisions on the one hand and ensuring accurate placement on the other.

[0039] The apparatus is preferably adapted to move the support substrate relative to the positioner along an x-direction extending perpendicular to the axis of rotation. The apparatus is also adapted to move the support substrate relative to the positioner along a y-direction extending perpendicular to both the x-direction and the axis of rotation. In this way, the nanostructures can be efficiently transferred to a plurality of devices arranged adjacent to each other.

[0040] The present invention also relates to a method for attaching nanostructures, in particular carbon nanotubes, to a device substrate, in particular by means of an apparatus as described above, wherein the nanostructures are respectively arranged between a pair of cantilevers supporting a substrate as described above, the cantilever pairs extending in different, non-parallel directions in a common plane, and wherein the method comprises at least the following steps:

[0041] - rotating the support substrate about a rotation axis extending perpendicularly through the common plane so as to sequentially bring the nanostructure from the support substrate to a plurality of attachment points on the device substrate so as to attach the nanostructure to the device substrate.

[0042] For attaching the nanostructure to the device substrate, the rotation axis is preferably tilted relative to the geometric normal of the device substrate plane in which the attachment point is arranged. In this way, collisions can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, which are intended to illustrate the current preferred embodiments of the present invention rather than to limit them. In the accompanying drawings,

[0044] Figure 1 shows a perspective view of a growth substrate according to the prior art in a starting position for transferring nanostructures to two devices arranged on a common device substrate;

[0045] Figure 2 shows the transfer of nanostructures to devices Figure 1 A three-dimensional diagram of a growth substrate and a device substrate;

[0046] Figure 3 The nanostructures are transferred to the device. Figure 1 A three-dimensional diagram of a growth substrate and a device substrate;

[0047] Figure 4a shows a top view of a growth substrate according to an embodiment of the present invention;

[0048] Figure 4b Shown by Figure 4a an enlarged detailed view of the rectangular area marked by dashed lines in FIG. 1 , wherein a plurality of radially extending portions of the growth substrate are identifiable;

[0049] Figure 4c Shown by Figure 4b an enlarged detailed view of the rectangular area marked by the dashed line in FIG, wherein a single radially extending portion of the growth substrate is identifiable;

[0050] Figure 4d Shown by Figure 4c An enlarged detailed view of the rectangular region marked by dashed lines in FIG. 1 , wherein the cantilever pairs of radially extending portions of the growth substrate identifiably include nanostructures held by some of the cantilever pairs;

[0051] Figure 5a It is shown that with the help of Figure 4a A perspective view of an apparatus according to an embodiment of the present invention during attachment of a nanostructure to a device substrate by a growth substrate;

[0052] Figure 5b Shows Figure 5a A side view of the device;

[0053] Figure 5c Shows Figure 5a Top view of the equipment;

[0054] Figure 5d Shown by Figure 5c An enlarged detail view of the rectangular area marked by the dashed line in FIG. 1 ; and

[0055] Figure 5e Shown by Figure 5d Magnified detail view of the rectangular area marked by the dashed line. DETAILED DESCRIPTION

[0056] Figures 1 to 3 A support substrate in the form of a growth substrate 1 according to the prior art is shown in different positions relative to a device substrate 3. It can be seen that the prior art growth substrate 1 has a flat rectangular shape overall and comprises a plurality of cantilever pairs 13 arranged in parallel along one side of a main portion 14 of the growth substrate 1. In each case, a nanostructure 2, which may be in the form of a carbon nanotube, is held between at least a portion of the cantilever pairs 13. The nanostructure 2 preferably extends perpendicularly relative to the extension of the cantilever.

[0057] The device substrate 3 includes a plurality of devices 31, which are usually arranged in rows of several devices 31 adjacent to each other in parallel, such as from, for example Figure 5c In order to transfer the nanostructure 2 to the device 31, the growth substrate 1 is positioned close to the device substrate 3 in such a way that the cantilever pair 13 holding the nanostructure 2 is arranged above the device to which the corresponding nanostructure 2 is to be attached ( Figure 1 ). Then, follow the Figure 1 The growth substrate 1 is lowered relative to the device substrate 3 in the direction indicated by the arrow in FIG. 1 until the nanostructure 2 contacts the device 31 in the desired position and orientation ( Figure 2 ). The growth substrate 1 is then further lowered and moved away from the device substrate 3. In doing so, the nanostructures 2 remain in their positions on the device 31, as shown in FIG. Figure 3 It can be seen in.

[0058] The device 31 to which the nanostructure 2 is attached may, for example, form a transistor or another electronic circuit. Figure 3 As shown, nanostructures 2 may in particular be in the form of carbon nanotubes, which are placed on a device 31 forming a transistor in such a way that the drain 32 of the device 31 is connected to the source 33. The locations on the device substrate 3 where the nanostructures 2 are to be attached are referred to as attachment points 34.

[0059] from Figure 1 It can be seen that the length of the growth substrate 1 along the side including the cantilever pair 13 is limited by the distance d between the devices 31: if the length of the growth substrate 1 is too long, the cantilever pair 13 collides with the adjacent device 31. Typically, the device substrate 3 is in the form of a wafer of a given size (see Figure 5c ), which means that increasing the distance d between devices 31 can only be achieved at the expense of fewer devices 31 per wafer. Therefore, with prior art growth substrates 1, the scalability towards industrial production of large numbers of identical or similar devices is limited.

[0060] Figures 4a to 4d A support substrate in the form of a growth substrate 1 according to an embodiment of the present invention is shown. Since the support substrate here not only plays the role of supporting the nanostructures 2, but also plays the role of pre-growing them, the support substrate is referred to as a growth substrate 1. In other embodiments, it is of course also possible that the nanostructures 2 are not grown on the support substrate, but grow elsewhere, and the support substrate only plays the role of supporting the nanostructures 2 so as to transfer them to the device substrate. Therefore, Figures 4a to 4d The growth substrate 1 shown in FIG. 1 may generally also be a support substrate which is not used for growing nanostructures.

[0061] from Figure 4a As can be seen, the growth substrate 1 has a generally flat, plate-like form with a circular, i.e. curved, periphery 11. The growth substrate 1 further comprises a plurality of radial extensions 15, each of which is connected to a main portion 14 of the growth substrate 1 and extends radially outwards therefrom. The main portion 14 forms a circular or annular area. The radial extensions 15 are arranged at a distance relative to each other along the periphery 11 of the growth substrate 1.

[0062] A plurality of cantilever pairs 13 are provided on each radially extending portion 15. Figure 4d The cantilever pairs 13 of each radially extending portion 15 together form a group 12 of a plurality of cantilever pairs 13 extending parallel to each other and arranged at regular distances relative to each other (see Figure 4b to Figure 4d ).

[0063] The radial extension portion 15 may be made of the same material as the main portion 14 in one piece. However, in some embodiments, it is also possible that the radial extension portion 15 having the cantilever pair 13 is made separately from the main portion 14 and is only attached to the main portion 14. In this case, the radial extension portion may be made of the same or different material as the main portion 14. In such an embodiment, it is even possible that the radial extension portion 15 is respectively made of a growth substrate 1 of the prior art (e.g., as Figures 1 to 3Since the radially extending portion 15 is attached to the periphery 11 of the main portion 14, the main portion 14 and the radially extending portion 15 together form the growth substrate 1 according to the embodiment of the present invention.

[0064] The configuration of the cantilever pair 13 along the curved periphery 11 of the growth substrate 1 brings the following advantages: Figures 1 to 3 Compared to the prior art growth substrate 1 of the present invention, the growth substrate 1 can have a greater number of cantilever pairs 13. Due to the curved periphery of the growth substrate and the non-parallel extension of the group 12 of cantilever pairs 13, there is no risk of collision with adjacent devices 31 during the transfer of the nanostructure 2 to the device 31.

[0065] Figure 5a to Figure 5e A preferred embodiment of an apparatus 4 for attaching a nanostructure 2 that has been grown or deposited on a support substrate of the present invention to a device substrate 3 is shown. The support substrate may be, for example, Figures 4a to 4d The form of the growth substrate 1 is shown.

[0066] The device 4 comprises a holder 41 for holding a growth substrate 1 (preferably in such a way that the growth substrate 1 can be released from the holder 41). The holder 41 is attached to a rotating disk 42 of the device 4. The rotating disk 42 can rotate around a rotation axis R together with the holder 41 and the growth substrate 1 attached thereto. The rotating disk 42 is in turn attached to a pivot block 43 of the device 4, which allows the rotating disk 42 to be tilted at an inclination angle α, thereby allowing the rotation axis R to be tilted relative to a geometric normal N of the device substrate 3. The geometric normal N is defined by a device substrate plane P, and the attachment point 34 of the device substrate 3 is arranged in the device substrate plane P. In this case, the device substrate plane P coincides with the flat upper surface of the device substrate 3. The pivot block 43 is pivotably attached to a connection block 44 held by a mounting bracket 45.

[0067] The device substrate 3 is held by a positioner 46 , which may be, but need not be, fixed. The positioner 46 is used to hold and position the device substrate 3 relative to the growth substrate 1 .

[0068] The ability to rotate the growth substrate 1 allows one nanostructure 2 held by the pair of cantilevers 13 to be transferred to the device substrate 3 at a time.

[0069] The inclination of the rotation axis R relative to the normal N allows a particularly precise transfer of the nanostructure 2 to the device 31, significantly reducing the risk of collisions of the growth substrate 1 or parts of the apparatus 4 with the device substrate 3. In this respect, reference is made to Figure 5b , where it can be seen that, due to the inclination of the rotation axis R relative to the normal N of the device substrate 3 , only a small portion of the periphery 11 of the growth substrate 1 is in contact with the device substrate 3 .

[0070] In order to bring the nanostructures 2 to the plurality of attachment points 34 where they will be attached to the device substrate 3, as Figure 5a and Figure 5b The mounting bracket 45 and thus the device 4 can be arranged in the x-direction and the y-direction ( Figure 5a The x-direction and the y-direction extend perpendicularly to each other and respectively perpendicularly to a geometric normal N of a device substrate plane P in which the attachment point 34 is arranged.

[0071] In certain embodiments, Figure 5a and Figure 5b The device 4 shown can also be rotated as a whole about an axis of rotation R. Such a rotation of the entire device 4 can be advantageous in order to correct alignment errors before transferring the nanostructures 2 .

[0072] Figure 5d and Figure 5e Detailed views of the growth substrate 1 and the device substrate 3 are shown during the transfer of the nanostructures 2 through the apparatus 4. Figure 5d and Figure 5e , the ability to precisely position a certain cantilever pair 13 of a growth substrate 1 relative to a device substrate 3 becomes particularly evident: due to the curved perimeter of the growth substrate 1, only a single radial extension 15 of a group 12 with a corresponding cantilever pair 13 is in contact with the device substrate 3. The fork length l of each radial extension 15 measured perpendicularly to the extension of the corresponding cantilever pair 13 is dimensioned to be shorter than the distance d between the devices 31. In this way, there is no risk of a radial extension 15 colliding with an adjacent device 31 during the transfer of the nanostructures 2. The nanostructures 2 held by the same group 12 of cantilever pairs 13 can be transferred one by one to the device substrate 3 before the growth substrate 1 is rotated about the rotation axis R in order to transfer the nanostructures 2 of another group 12 to the device substrate 3. In this way, a large number of nanostructures 2 of multiple groups 12 can be transferred without having to replace the growth substrate 1.

[0073] The invention is of course not limited to the embodiment shown in the figures. Various modifications are possible. For example, the main part 14 of the support substrate or growth substrate does not necessarily have to have a circular perimeter. Alternatively, it can also have a polygonal perimeter, such as a triangle, square or rectangle or any other polygonal perimeter with more than four corners / sides. The cantilever pair does not necessarily have to be configured along the entire perimeter 11, but can also be configured along only a part of the perimeter. Further modifications are possible.

[0074] Reference numerals list

[0075] 1 Growth substrate 41 Holding member

[0076] 11 circumference 42 rotating disk

[0077] 12 sets of 43 pivot blocks

[0078] 13 cantilever to 44 connection block

[0079] 14 Main part 45 Mounting bracket

[0080] 15 radial extension portion 46 positioner

[0081] 2 Nanostructure R rotation axis

[0082] xx Direction

[0083] 3Device substrate yy direction

[0084] 31 Device α tilt angle

[0085] 32Drain dDevice distance

[0086] 33 Source I fork length

[0087] 34 Attachment point N Normal

[0088] P Device substrate plane

[0089] 4 Equipment

Claims

1. A support substrate (1) for a nanostructure (2), in particular for carbon nanotubes, the support substrate (1) comprising a plurality of cantilever pairs (13), between each cantilever pair being suitable for holding a nanostructure (13), Features At least some of the plurality of cantilever pairs (13) are configured along at least a curved or angled portion of the periphery (11) of the support substrate (1) such that the at least some of the cantilever pairs extend in different, non-parallel directions.

2. The support substrate (1) according to claim 1, wherein: The plurality of cantilever pairs (13) are distributed along the entire periphery (11) of the supporting substrate (1).

3. The support substrate (1) according to claim 1 or 2, wherein: Each of the cantilevered arms (13) extends outwardly in an approximately radial direction.

4. The support substrate (1) according to any one of the preceding claims, wherein The periphery (11) of the support substrate (1) is in the overall shape of a circle or a regular polygon.

5. The support substrate (1) according to any one of the preceding claims, wherein The cantilever pairs (13) are arranged in a group (12) of a plurality of cantilever pairs (13) extending parallel to each other.

6. The support substrate (1) according to claim 5, wherein: A group (12) of a plurality of cantilever pairs (13) extending parallel to each other is arranged at regular intervals and preferably along the entire periphery (11) of the support substrate (1).

7. The support substrate (1) according to claim 5 or 6, wherein: The angle between any two adjacent groups (12) of cantilever pairs (13) extending parallel to each other is not greater than 10°, preferably not greater than 8°, more preferably not greater than 6°.

8. The support substrate (1) according to any one of the preceding claims, wherein The plurality of cantilever pairs (13) extend in a common plane.

9. A device (4) for attaching nanostructures (2), in particular carbon nanotubes, to a device substrate (3), the device (4) comprising: a holder (41) for holding a support substrate (1) according to any one of the preceding claims, the support substrate comprising a plurality of cantilever pairs (13) extending in different, non-parallel directions in a common plane; as well as a positioner (45) for positioning the device substrate (3) to which one or more nanostructures (2) are attached relative to the support substrate (1); wherein the apparatus (4) is adapted to move the holder (41) and the positioner (45) relative to each other in such a manner that the nanostructures (2) respectively held between the cantilever pairs (13) are brought from the support substrate (1) to a plurality of attachment points (34) on the device substrate (2) so as to be attached to the device substrate (2), Features The apparatus (4) is adapted to rotate the support substrate (1) about a rotation axis (R) extending perpendicularly through a common plane of the plurality of cantilever pairs (13) so as to sequentially attach the nanostructures (2) to the device substrate (3).

10. The device (4) according to claim 9, wherein: The rotation axis (R) is tilted or tiltable relative to a geometric normal (N) to a device substrate plane (P) on which the attachment point (34) is arranged.

11. The device (4) according to claim 10, wherein: The rotation axis (R) is tilted or tiltable at an inclination angle (α) in the range of 1° to 40°, preferably in the range of 4° to 20°, in particular in the range of 4° to 10°, relative to the geometric normal (N) of the device substrate plane (P).

12. The device (4) according to any one of claims 9 to 11, wherein: The device (4) is adapted to move the support substrate (1) relative to the positioner (45) along an x-direction (x) extending perpendicularly to a geometric normal (N) to a device substrate plane (P) where the attachment points (34) are arranged.

13. The device (4) according to claim 12, wherein: The device (4) is further adapted to move the support substrate (1) relative to the positioner (45) along a y-direction (y) extending perpendicularly to both the x-direction (x) and the geometric normal (N).

14. A method for attaching nanostructures (2), in particular carbon nanotubes, to a device substrate (3), in particular by means of an apparatus (4) according to any one of claims 9 to 13, wherein the nanostructures (2) are respectively arranged between pairs of cantilevers (13) of a support substrate (1) according to any one of claims 1 to 8, the pairs of cantilevers (13) extending in different, non-parallel directions in a common plane, and wherein the method comprises at least the following steps: - rotating the support substrate (1) about a rotation axis (R) extending perpendicularly through the common plane so as to sequentially bring the nanostructures (2) from the support substrate (1) to a plurality of attachment points (34) on the device substrate (3) so as to attach the nanostructures (2) to the device substrate (3).

15. The method according to claim 14, wherein: In order to attach the nanostructure (2) to the device substrate (3), the rotation axis (R) is tilted relative to a geometric normal (N) to a device substrate plane (P) where the attachment point (34) is arranged.

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