DEVICE AND METHOD FOR DETERMINING THE PENETRATION OF A PARTICLE INTO A MATERIAL

Description

[0001] The present invention relates to a device for determining the penetration of a particle into a material according to the preamble of claim 1 and a method for determining the penetration of a particle into a material according to the preamble of claim 13.

[0002] The deterministic implantation of single ions is one of the key techniques for fabricating quantum systems, and especially quantum computers, in a solid. With ever-shrinking devices, the deterministic implantation of ions and their controlled placement are also of interest for conventional metal-oxide field-effect transistors (MOSFETs). Furthermore, optical centers, such as the nitrogen-vacancy center in diamond, are being researched for use in quantum computers or as single-photon sources. Here, too, deterministic ion implantation offers a crucial advantage for simplifying the fabrication of such devices.

[0003] Currently, there are two different classes of methods to achieve deterministic implantation: one via post-detection and the other via pre-detection.

[0004] In so-called post-detection, secondary electrons, which are released when an ion strikes a surface, are detected. The presence of such secondary electrons is therefore a measure of ion implantation. Alternatively, electron-hole pairs can also be extracted using a diode and thus detected.

[0005] In both cases, however, it is a disadvantage that the detection must be 100% successful, because otherwise ions would be duplicated. To generate measurable effects, high kinetic energies of the ions must be used, but due to these high kinetic energies, the lateral resolution is limited by straggling. Furthermore, the applicability of this method is limited to certain substrates. Finally, straggling at high kinetic energies makes it difficult to utilize the lattice defect in subsequent applications.

[0006] Such post-detection is shown, for example, in EP 1 747 579 B1 and CN 109 786 198 A.

[0007] In so-called predetection, the ion is detected before it even reaches the target. The target is protected, for example, by a gate voltage, so that ions cannot normally reach it. The gate is only opened if the ion has been unambiguously identified beforehand.

[0008] In this case, "false positive" signals are not possible, but "false negative" signals can occur if an ion is selected but does not reach the target substrate, resulting in a defect without a foreign atom that would have to be reworked in a second step.

[0009] Such predetection is shown, for example, in US 5 539 203 A and CN 109 920 713 B.

[0010] This predetection technique is currently used in ion traps, where individual ions are identified and individually fired from the source. It is also employed in the image charge method, which utilizes the effect that charged particles generate image charges that are then detected by highly sensitive detectors. However, in both cases, detection in front of the target is necessary, making these methods technically very demanding and therefore, to date, only implemented on a research scale.

[0011] Furthermore, all methods based on post-detection or pre-detection to date can only be used sequentially and are therefore not suitable for high throughput.

[0012] US Patent 5,451,529 A discloses a method for real-time monitoring of ion implantation doses. This method uses the increase in the resistance of a metal silicide layer after ion implantation to control ion doses in the range of 10<13 to 10<16 ions cm-2.

[0013] It is therefore an object of the present invention to provide a device and a method with which the penetration of particles into a material can be detected quickly and reliably. In particular, the method should enable particles to be implanted deterministically into a substrate in such a way that high spatial resolution and high throughput are possible. Preferably, a deterministic particle source should be implemented in a simple and cost-effective manner.

[0014] This problem is solved with the device according to claim 1 and the method according to claim 13. Advantageous embodiments are specified in the dependent claims and in the following description together with the figures.

[0015] The inventors recognized that this problem could be solved surprisingly easily by combining neither pure post-detection nor pure pre-detection methods. This is achieved by placing a first layer between the material and the particle source, relative to the direction of the particle's beam as it penetrates the material. After the particle passes through this layer, its ohmic resistance changes, allowing the particle's passage and thus its penetration into the material to be detected by measuring this change in resistance. The penetration of a single particle can therefore be reliably determined. The first layer can be placed directly on the material or spaced apart. This spacing can consist of one or more intermediate layers or simply be a gap.

[0016] Therefore, this is not pure pre-detection, because the particle has already penetrated the material at the time the change in resistance is measured. However, it is also not pure post-detection, because the effects of the particle's penetration into the material are not determined. Thus, this is a novel combination of both methods.

[0017] The device according to the invention for determining the penetration of a particle from a particle source into a material is characterized in that a first layer is arranged between the particle source and the material, the resistance of which changes when the particle penetrates the first layer, and the device includes means for determining the change in resistance of the first layer. The determination of the change in resistance of the first layer can be carried out, for example, by means of a four-point measurement.

[0018] In an advantageous further development, it is stipulated that the first layer and the material differ in their chemical composition. This makes penetration particularly easy to detect.

[0019] In a further advantageous embodiment, the first layer and the material are arranged at a distance from each other. The detection is still particularly effective in this case. If an electrically insulating layer is placed between the material and the first layer, the detection is possible even if the material is conductive.

[0020] In an advantageous embodiment, the first layer is designed such that its ohmic resistance changes permanently after the particle passes through it, preferably through the disruption of its lattice structure. If the first layer consists of graphene or graphite, for example, the transverse conductivity differs significantly from the vertical conductivity due to the lattice order of this layer structure. This lattice structure would be permanently disrupted by a passing particle, resulting in a permanent change in conductivity. This allows for long-term detection, which is a significant advantage over, for example, the post-detection methods according to EP 1 747 579 B1 and CN 109 786 198 A, since electron-hole pairs are only generated and destroyed very briefly in those methods. In contrast, the device according to the invention allows for the detection of the resistance change at any later time.

[0021] A further advantage over this type of post-detection is that no cooling of the material is required; the principle of the present invention also works at room temperature. Furthermore, any material can be used because no electron-hole pairs need to be generated within it; instead, detection occurs via the first layer. Therefore, the material does not necessarily have to be a semiconductor.

[0022] In a further advantageous embodiment, the first layer is arranged on the material. This allows for particularly reliable detection of penetration. The first layer can be applied directly to the material or with an interlayer of other layers, such as an electrically insulating layer.

[0023] In an advantageous further development, the first layer is designed as a lattice structure. This allows many areas on the material to be electrically monitored simultaneously for particle penetration, thus enabling parallel determination of the penetration.

[0024] In a particularly advantageous embodiment, the first layer is a layer whose electrical resistance changes with respect to an undisturbed state compared to a state with an atomic lattice defect. In particular, the first layer exhibits semiconductor properties and has a small energy gap (preferably less than or equal to 0.2 eV) and a very low conduction electron density (preferably less than or equal to 1018 cm-3) at room temperature. This allows penetration to be reliably detected even for very low kinetic particle energies. Preferably, the first layer decreases its electrical resistance after a particle has passed through it. Alternatively, it could also be a layer that increases its resistance.

[0025] According to the invention, the first layer comprises one of the following materials: graphite, graphene, bismuth, zinc telluride, silver selenide, and mercury telluride. In these materials, even single atomic lattice defects cause a large and lasting change in ohmic resistance, so that even small particles with low energy can be easily determined.

[0026] In a particularly advantageous embodiment, the first layer has a thickness in the range of 5 nm to 100 nm, preferably in the range of 15 nm to 25 nm. This allows for very good particle detection without causing excessive disturbance to the particle on its way to the material, thus ensuring, among other things, precise particle positioning.

[0027] In a particularly advantageous embodiment, the first layer is arranged in an island-like form, with the islands connected via electrical conductors for resistance determination. The islands preferably have a larger dimension than the conductors. The width and height of the conductors are preferably in the range of 5 nm to 5 µm. This allows for particularly effective parallelization of individual material regions that are obscured by the islands or shadowed with respect to the particle stream. The islands can be rectangular, round, oval, or similar in shape. The conductors and the islands can be made of the same material (for example, both of graphite), but this is not required (for example, the islands could be made of graphite and the conductors of a metal). In this context, the term "material" is used to distinguish it from the "material" into which the particles are implanted.In fact, "fabric" refers to a specific material.

[0028] The electrical lines can also be used to control a quantum computer or quantum system. For example, one could apply an alternating voltage to the electrical lines to generate microwaves that would excite specific energy levels of low voltage centers.

[0029] In a further advantageous embodiment, the islands are provided to each have a dimension in the range of 1 nm x 1 nm to 500 nm x 500 nm, preferably a dimension in the range of 10 nm x 10 nm to 100 nm x 100 nm, more preferably a dimension in the range of 15 nm x 15 nm to 50 nm x 50 nm, and more preferably a dimension in the range of 20 nm x 20 nm to 30 nm x 30 nm. Particles can then be implanted into the material in such a grid that quantum systems and ultimately quantum computers can be created.

[0030] In a particularly advantageous embodiment, the islands are spaced apart in the range of 10 nm to 500 nm, preferably in the range of 20 nm to 100 nm, and especially in the range of 40 nm to 60 nm. This allows particles to be implanted into the material in such a grid that quantum systems and ultimately quantum computers can be created.

[0031] In a further advantageous development, at least one electrode is provided. This allows for the generation of sufficiently strong opposing fields for electrically charged particles with relatively low energies, such that after the detection of a particle that has penetrated the material at the location of the first layer, further particles are prevented from penetrating the material by the generated opposing field. This enables deterministic particle implantation in a simple and cost-effective manner, provided the electrode is switched depending on the detection of a particle. In this way, effective opposing fields can be generated for particles with energies of 100 keV or less.

[0032] This electrode can be positioned on the side of the first layer opposite the material, between the first layer and the material, or on the side of the material opposite the first layer. If the electrode is too thick and obstructs the path of a particle to be implanted, thus acting as a mask for the particle, at least one opening should be provided in the electrode to allow the particle to pass through it. The electrode itself can also be used as a mask.

[0033] If there are multiple openings for implanting particles at different locations, then each opening would have to be assigned its own electrode.

[0034] A counter electrode must be provided for the electrode in the usual manner, which could, for example, be arranged at the particle source.

[0035] In a further advantageous development, the particle source is arranged to be movable relative to the material. This also allows for deterministic particle implantation to be achieved in a simple and cost-effective manner, as the position of the particle source above the material is changed depending on the detection of a particle, preventing the implantation of another particle at the location of an already implanted particle. An advantage of using such a movable particle source is that only the first layer, i.e., the detection layer, is required. "Relatively movable" in this context means that one of the two elements—material and particle source—moves relative to the other, while the other element is either stationary or can also be moved.

[0036] In an advantageous embodiment, the particle source is provided with an aperture consisting of an AFM cantilever. This allows the particle source to target areas on the material with exceptional precision and allow particles to penetrate them. Such a device is shown in CN 109 920 713 B, the relevant content of which is incorporated in its entirety. In contrast to the present invention, however, CN 109 920 713 B describes a predetection process in which a single ion is trapped in an ion trap before the implantation of this ion into a substrate takes place.

[0037] In an advantageous embodiment, at least one mask is arranged on the side of the first layer opposite the material. This mask is impermeable to the particle at selected kinetic energies. Preferably, the mask at least partially covers the first layer and, in particular, has at least one opening that defines a channel for guiding the particle through it. This allows for precise localization of the particle's implantation within the material. The mask material can also cover the electrical conductors that contact the first layer for resistance measurement. If an electrode is used to generate a counter-field, the electrode can simultaneously form the mask.

[0038] In a further advantageous embodiment, the opening of the mask is provided to be less than or equal to 100 nm, preferably less than or equal to 50 nm, more preferably less than or equal to 10 nm, and particularly less than or equal to 5 nm. This results in very high spatial accuracy and, furthermore, allows the desired grid between these implanted particles to be reproduced very precisely in the case of multiple implantation areas.

[0039] In a further advantageous development, the mask is provided for in the form of a thermoplastic, preferably PMMA. This allows the mask to be manufactured particularly easily and cost-effectively. In particular, very small, defined openings can be created in it using, for example, a lithography process.

[0040] In a further advantageous embodiment, at least one second layer, meltable by heating, is provided, which is impermeable to the particle at the selected kinetic energies. This second layer can be identical to the mask, but need not be. The second layer could therefore itself form the mask or be arranged such that its melting causes an opening in the mask to close. The second layer thus does not need to have an opening identical to that of the mask, although it can. If the second layer is arranged in relation to the opening such that, after melting, it penetrates and / or covers the opening, the second layer need not have an identical opening, but can, for example, be located on one side next to the opening in the mask.Typically, the opening in the mask can be produced very precisely using lithographic methods, while this will not be possible with the same precision in the second layer, for example, using etching. Therefore, the opening in the second layer will likely be larger than the openings in the mask.

[0041] In a further advantageous embodiment, the second layer is located adjacent to, preferably directly adjacent to, the mask in order to optimally seal the mask opening, with the second layer preferably being positioned between the material and the mask. This makes it particularly easy to cover or seal an opening in the mask with the molten material of the second layer (when the material of the second layer penetrates the opening).

[0042] This also allows for a simple and cost-effective deterministic particle implantation: after determining the penetration of a particle, the second layer is immediately melted, thereby sealing any opening in the mask and preventing the implantation of another particle at the site of an already implanted particle. This fused layer can also cover the electrical conductors of the first layer, if necessary.

[0043] In a further advantageous embodiment, a heating element is provided for heating the second layer. This heating element can, for example, be a separate layer, but it could also be formed by the first layer if the latter is an ohmic heater such as graphite. In this case, the resistance measurement leads could be used to power the heating element. This allows the second layer to be melted particularly easily. If the heating element is formed by the first layer, the device has a particularly compact design. Alternatively, instead of a separate heating element, the second layer could be melted using a laser beam or an electron beam.

[0044] In a further advantageous embodiment, the second layer has a melting point of less than or equal to 100 °C. This allows the melting of the second layer, and thus the prevention of further particle penetration, to be achieved particularly quickly, resulting in very short response times for the device.

[0045] In a further advantageous embodiment, the second layer comprises one of the substances from the group consisting of wax and polymer, with the polymer preferably being polycaprolactone (PCL). This allows the second layer to be produced particularly simply and cost-effectively.

[0046] In a further advantageous development, it is envisaged that the material comprises one of the substances from the group: diamond, SiC, silicon, TiO₂ and ZnO. This makes it particularly easy to create quantum systems.

[0047] Independent protection is claimed for the inventive method for determining the penetration of a particle from a particle source into a material, characterized in that a first layer is arranged between the particle source and the material, the resistance of which changes when the particle penetrates the first layer, and the change in resistance of the first layer is determined. If a change in resistance of the first layer is then detected, for example in the context of a four-point measurement, the implantation of such a particle can be inferred.

[0048] In an advantageous further development, it is provided that the device according to the invention is used. This makes the method according to the invention particularly easy to implement.

[0049] In a further advantageous embodiment, the material is held in a vacuum, with the maximum pressure preferably being less than or equal to 0.0001 mbar. This further increases the spatial precision because the particle is not subjected to unnecessary collisions with atmospheric particles, which can negatively affect both lateral positional and depth precision.

[0050] In a further advantageous development, it is envisaged that the material comprises one of the substances from the group: diamond, SiC, silicon, TiO₂ and ZnO. This makes it particularly easy to create quantum systems.

[0051] In a further advantageous embodiment, the method is used for deterministic ion implantation, preferably for the generation of quantum systems. For this purpose, the second layer could again be used to prevent further ion irradiation. This prevention could also be achieved by an electrode, for example, in the form of a mask or at the particle source, such that applying a voltage to it prevents the penetration of further particles into the material. A deterministic particle source, whose particle emission can be precisely controlled, could also be used for this purpose.

[0052] In an advantageous further development, it is provided that the method is used for spatially resolved single particle detection.

[0053] In a further advantageous development, the method is used for spatially resolved mass spectrometry. Individual ions are identified by detecting the change in resistance.

[0054] In an advantageous embodiment, the method is used to generate magnetic moments in the material and, preferably, to detect them by measuring the local magnetoresistance of the first layer. The necessary deterministic implantation of defects or ions with magnetic moments would be carried out by the method according to the invention. Depending on the area of ​​the islands in the first layer, the detection of a magnetic moment of one µB (one Bohr magneton) would be possible. More precisely, a change in resistance due to a magnetic field, i.e., the magnetoresistance, can be measured directly after implantation if the defect or the implanted ion has a magnetic moment. This magnetic moment generates a stray field on the surface of the sample, and this field influences the resistance of, for example, the first layer (e.g., a graphite layer).The smaller the area of ​​the first layer, the better the sensitivity to the stray field, provided the contacts are also closer together. This change is independent of time, as the stray field is always present.

[0055] In a further advantageous embodiment, the method is used for ion beam-based materials research. This involves the possibility of implanting individual ions of different masses onto various materials. With the method according to the invention, it will then be possible to better investigate the effects produced on the implanted material, e.g., penetration depth versus ion energy up to the point of inducing disorder (defects) in the material lattice. Thus, these individual ions can be implanted deterministically, and the effect of this implantation on the material can be investigated using other methods.

[0056] The inventive method can also be used for alpha particle detection.

[0057] Furthermore, independent protection is claimed for the inventive use of the inventive device for the manufacture of a detector for mass spectrometry, a detector for single particle implantation, an information storage device or a component for a quantum computer, preferably a processor for a quantum computer.

[0058] At the same time, independent protection is also claimed for a detector for mass spectrometry, a detector for single particle implantation, an information storage device and a component for a quantum computer, preferably a processor for a quantum computer, which comprise the device according to the invention.

[0059] In summary, it can be stated that the present invention can be used for numerous applications: Firstly, pure particle detection can be carried out. For this, only the first layer is necessary.

[0060] Alternatively, deterministic particle implantation can be achieved by blocking the location where a particle is implanted from subsequent particles.

[0061] This blocking can be achieved through an electrostatic barrier or a material barrier.

[0062] Within the framework of material barrier technology, the melting of a second layer is possible, which could be achieved through ohmic heating, but also through energy input via a laser beam or an electron beam. Material barrier technology can also be achieved by growing a specific material, for example, from a precursor gas in combination with an electron beam or an ion beam.

[0063] Finally, deterministic particle implantation can also be achieved using a movable ion beam source, which is switched off or moved away after a desired implanted particle has been detected.

[0064] These approaches can also be combined.

[0065] Furthermore, the device according to the invention can also be used to manufacture detectors for mass spectrometry, detectors for single particle implantation, information storage devices in general, and components for a quantum computer, preferably processors for a quantum computer.

[0066] The features and further advantages of the present invention will become clear below with reference to the description of two preferred embodiments in conjunction with the figures. These figures show, purely schematically: Fig. 1 shows the sensor according to the invention according to a first preferred embodiment in a partial cross-sectional view, Fig. 2 shows the sensor according to the invention. Fig. 1 in a partial top view, Fig. 3 the sensor according to the invention Fig. 1 in a top view, Fig. 4 the sensor according to the invention Fig. 1in a first operating state, Fig. 5 the sensor according to the invention Fig. 1 in a second operating state, Fig. 6 the sensor according to the invention Fig. 1 in a third operating state, Fig. 7 the sensor according to the invention Fig. 1 in a fourth operating state, Fig. 8 the sensor according to the invention according to a second preferred embodiment in a partial cross-sectional view, Fig. 9 the sensor according to the invention Fig. 8 in a first operating state, Fig. 10 the sensor according to the invention Fig. 8 in a second operating state and Fig. 11 the sensor according to the invention according to a third preferred embodiment in a partial cross-sectional view.

[0067] In the Fig. 1 , 2 and 3 The device 10 according to the invention is shown as a sensor 10 according to a first preferred embodiment in various views.

[0068] It can be seen that the sensor 10 has a substrate 12 on which a first layer is arranged in an island-like pattern 14, 14a, 14b, 14c, ..., 14n. These islands 14, 14a, 14b, 14c, ..., 14n are arranged in a grid pattern and each is contacted with electrical conductors 16, 16a, 16b, 16c, ..., 16n, 18, 18a, 18b, 18c, ..., 18n, resulting in a grid structure 20.

[0069] The lines 16, 16a, 16b, 16c, ..., 16n, 18, 18a, 18b, 18c, ..., 18n are covered by a mask material 22.

[0070] On islands 14, 14a, 14b, 14c, ..., 14n there is a second layer 24, which has a central opening 26 above each island 14, 14a, 14b, 14c, ..., 14n.

[0071] On the second layer 24 is a mask 28, which, identical to the central opening 26 of the second layer 24, has a central opening 30. The respective central openings 26, 30 of the second layer 26 and mask 28 are thus arranged in a line above the corresponding island 14, 14a, 14b, 14c, ..., 14n.

[0072] In the Fig. 2 and 3 Only the grid structures 20, 20a, 20b, 20c, ..., 20n arranged on the substrate 12 with the first layer 14, 14a, 14b, 14c, ..., 14n and the electrical conductors 16, 16a, 16b, 16c, ..., 16n, 18, 18a, 18b, 18c, ..., 18n are shown, but not the mask material 22, the second layer 24 and the mask 28.

[0073] Sensor 10 can - as in Fig. 3 shown - with numerous lattice structures 20a, 20b, ... 20n, however, the lattice structures 20a, 20b, ... 20n could also be directly connected to each other, so that the in Fig. 2shown grid structure 20 over the entire substrate 12 in Fig. 3 stretches.

[0074] The substrate 12 can, for example, be a diamond layer. The first layer 14 is preferably a graphite layer with a thickness of 5 nm to 100 nm, more preferably 15 nm to 25 nm.

[0075] The islands 14, 14a, 14b, 14c, ..., 14n have a square shape with an edge length in the range of 1 nm to 500 nm, preferably in the range of 20 nm to 30 nm. The islands 14, 14a, 14b, 14c, ..., 14n are spaced apart from each other by 10 nm to 500 nm, preferably by 40 nm to 60 nm. However, the shape of the islands 14, 14a, 14b, 14c, ..., 14n can also be round, oval, or the like.

[0076] The electrical conductors 16, 16a, 16b, 16c, ..., 16n, 18, 18a, 18b, 18c, ..., 18n can be metallic, but in the illustrated embodiment they are also made of graphite, so that they can be produced in a single operation together with the islands 14, 14a, 14b, 14c, ..., 14n. The electrical conductors 16, 16a, 16b, 16c, ..., 16n, 18, 18a, 18b, 18c, ..., 18n thus have a length in the range of 10 nm to 500 nm, preferably in the range of 40 nm to 60 nm. Their width and height are in the range of 5 nm to 100 nm, preferably from 15 nm to 25 nm.

[0077] Alternatively, instead of connecting the electrical lines 16, 16a, 16b, 16c, ..., 16n, 18, 18a, 18b, 18c, ..., 18n to the islands 14, 14a, 14b, 14c, ..., 14n in one plane, they could also be arranged below and / or above the islands 14, 14a, 14b, 14c, ..., 14n.

[0078] PMMA with a thickness in the range of 5 nm to 5µm is used as mask material 22 and as material for the mask 28.

[0079] The second layer 24 consists of a polymer and has a thickness in the range of 1 nm to 5 µm. Its melting point is 100 °C.

[0080] The openings 26, 30 have a circular cross-section with a diameter of less than 100 nm, preferably less than 50 nm, preferably less than 10 nm, and particularly less than 5 nm. However, the cross-section can also be rectangular, oval, or the like.

[0081] In connection with the Figs. 4 to 7 The functionality and use of sensor 10 will now be described.

[0082] In Fig. 4It can be seen that the sensor 10 is used in conjunction with a particle source 40 that emits particles 42a, 42b, 42c. The particles 42a, 42b, 42c strike the sensor 10 along their respective beam directions 44a, 44b, 44c, with the mask material 22 and the mask 28, respectively, preventing the particles 44b, 44c from penetrating the substrate 12. The thickness of the mask material 22 and the material of the mask 28 are selected such that the particles 44b, 44c are reliably stopped at the expected or desired kinetic energies.

[0083] Only particle 44a hits the openings 26, 30 exactly and can therefore penetrate the first layer 14 and enter the substrate 12.

[0084] The first layer 14 consists of graphite, whose electrical resistance changes with respect to an undisturbed state compared to a state with an atomic lattice defect. More precisely, the first graphite layer 14 exhibits semiconductor properties and possesses a small energy gap of 30 meV and a very low conduction electron density of ≤10 18 cm⁻³ at room temperature. This allows penetration to be reliably detected even for very low kinetic particle energies.

[0085] This detection of the particle 42a penetrating the first layer 14 is achieved by – as in Fig. 5 As shown, the sensor 10 with its electrical leads 16, 18 is conductively connected to an evaluation unit 50, which determines the electrical resistance 52 in the first layer 14 as part of a known four-point measurement.

[0086] When the particle 42a penetrates the first layer 14, one or more atomic lattice defects are created, causing the electrical resistance 52 of the first layer 14 to drop abruptly 54. This allows it to be reliably determined that the particle 42a has penetrated the first layer and thus entered the substrate 12.

[0087] As soon as this change in resistance is detected, energy is supplied to the first layer 14 via the electrical conductors 16, 18. This layer acts as an ohmic heater and heats up as a result. This heating to approximately 100°C melts the second layer 24, creating a closed second layer 24' in which the opening 26 of the second layer 24 is sealed (cf. Fig. 6 ). At the same time, the opening 30 of the mask 28 could also be closed by penetrating melt material of the second layer 24 (not shown).

[0088] In any case, the second layer 24' now acts as a protective layer, preventing newly irradiated particles 42d from penetrating the substrate 12. Therefore, the additional mask 28 could be omitted entirely, and only the second layer 24 could be used as a mask.

[0089] The determination of the intruding particle 42a (which takes approximately 1 µs after the actual penetration) as well as the closure of the opening 26 (which takes approximately 5 ms after the penetration is detected) are very fast, so that there is no danger of further particles 42a penetrating the substrate 12 in the meantime.

[0090] If the heating energy from the first layer 14 is insufficient, additional heating media (not shown) could also be used, which are designed, for example, as an additional ohmic heating layer.

[0091] On the other hand, instead of heating the second layer with an ohmic heater, a laser beam or an electron beam could also be used for melting.

[0092] Furthermore, the mask opening could also be closed by growth. For this purpose, a focused second ion beam or an electron beam in conjunction with a precursor gas could be used to close the openings 26 or 30 by material deposition from the precursor gas after an ion impact has been detected by sensor 10. For this, the ion beam used for ion implantation is briefly stopped and the corresponding opening 26 or 30 is closed before the implantation is continued.

[0093] In addition to spatially resolved electron or ion beam-assisted deposition of sealing material from a precursor gas, deposition can also be achieved using a perforated AFM tip. Another method would be mechanical sealing by material displacement using an AFM tip or by applying heat for melting via the AFM tip (e.g., with a diamond tip).

[0094] For a substrate with a very large number of mask openings (e.g., 1000), it would be advantageous to bundle the closing of the openings. After a suitable time, the resistance changes are determined using sensor 10, and these openings are closed simultaneously.

[0095] The sensor 10 thus ensures that only one particle 42a can penetrate the substrate 12 in a specific area of ​​the substrate 12, which is determined by the openings 26, 30 above the island 14.

[0096] With the help of the sensor 10, deterministic particle implantation with high spatial resolution can thus be carried out in a simple and cost-effective manner using an ordinary broadband particle source 40 (for example, a Kaufman ion source).

[0097] However, it is not necessary for the particle source to emit charged particles; it can also be neutral particles.

[0098] This can be used, for example, for the deterministic implantation of nitrogen, phosphorus, sulfur, carbon, boron or similar ions into diamond, silicon, silicon carbide or the like.

[0099] The lattice structure 20 makes this implantation highly parallel, since both the detection of the invading particle 42a and the closure of the openings 28 can be carried out independently (simultaneously or at different times) for all islands 14, 14a, 14b, 14c, ..., 14n.

[0100] Furthermore, after implantation, the sensor 10 itself can be used as a device with numerous quantum systems or for the construction of a quantum computer. In this case, the electrical lines 16 and 18 serve simultaneously for qubit control and readout.

[0101] In the Figs. 8 to 10 A second preferred embodiment of the sensor 100 according to the invention is shown in cross-sectional views.

[0102] It is in Fig. 8 It can be seen that this sensor 100 also has a substrate 102 on which an island-shaped first layer 104 is located, which is electrically contacted by electrical conductors 106. The mask material 108 is located on the electrical conductors.

[0103] In contrast to sensor 10, this sensor 100 does not have a second layer that can be melted, and the mask 110 with the central opening 112 above the first layer 104 is designed as an electrode, i.e., it consists of a metal that is electrically contacted.

[0104] If, in turn, this is appropriate Fig. 5 by detecting a sudden change in resistance of the first layer 104, it is determined that a particle 114 has penetrated the substrate 102 through the opening 112 (cf. Fig. 9 ), the penetration of further particles 116 can now be prevented by applying a voltage opposite to the charge of particle 116 to the electrode 110, whereby the particle 116 is repelled from the electrode 110 118 (cf. Fig. 10 ).

[0105] This also allows for the simple and cost-effective realization of deterministic particle implantation with high spatial resolution. However, this requires that the particle source emits charged particles so that these can be deflected by the electrode.

[0106] Mask 28, 110 and mask material 22, 108 could also be completely dispensed with if one follows the guidelines in Fig. 11 In the third preferred embodiment of the sensor 150 shown, the particle beam 152 is controlled, for example, by the tip 154 ​​of an AFM cantilever 156 in which an aperture 158 is provided, so that the high spatial resolution already exists in the particle beam 152 itself.

[0107] Then, using the first layer 160 and the electrical conductors 162, one only needs to determine the penetrating particle 162 in order to subsequently switch off the particle beam 152 and / or move the particle beam 152 to another location on the substrate 164 in order to implant the particle 162 there. This also results in deterministic particle implantation. Alternatively, one could again use a fused layer or an electrode.

[0108] It has become clear from the foregoing description that the present invention provides a method by which high spatial resolution of particles, in particular single-particle detection, can be achieved in a simple and cost-effective manner. This allows the penetration of particles into a material to be detected quickly and reliably. Furthermore, the present invention enables deterministic particle implantation to be realized in a simple and cost-effective manner.

[0109] The invention is defined exclusively by the attached claims.

[0110] The description serves only to illustrate possible embodiments and does not limit the scope of the claims. All features shown in the general description of the invention, the description of the exemplary embodiments, the following claims, and in the drawings can be essential to the invention, both individually and in any combination. These features or combinations of features can each constitute an independent invention, the right to claim which is expressly reserved. Individual features from the description of an exemplary embodiment need not necessarily be combined with one, more, or all other features specified in the description of that exemplary embodiment; any sub-combination is expressly disclosed in this respect.Furthermore, tangible features of the device can be reformulated and used as process features, and vice versa. Such a reformulation is therefore automatically disclosed. Reference symbol list

[0111] 10 Sensor according to a first preferred embodiment 12 Substrate, material 14, 14a, 14b, 14c, ..., 14 first layer, islands 16, 16a, 16b, 16c, ..., 16n, electrical conductors 18, 18a, 18b, 18c, ..., 18n electrical conductors 20, 20a, 20b, 20c, ...20n Lattice structure 22 Mask material 24 Second layer 26 Central opening 28 Mask 30 Central opening 40 Particle source 42a, 42b, 42c, 42d Particle 44a, 44b, 44c Beam direction 50 Evaluation unit 52 Electrical resistance of the first layer 14 54 Sudden drop in electrical resistance 52 100 Sensor according to the invention according to a second preferred embodiment 102 Substrate, material 104 First layer, island 106 Electrical conductors 108 Mask material 110 Mask, electrode 112 Central opening in mask 110 114 Penetrating particle 116 Further particles 118 Repulsion of particles 116 by electrode 110 150 Sensor according to the invention according to a third preferred embodiment 152 Particle beam 154 Tip of a AFM cantilevers 156 156AFM cantilever 158 Aperture 160 First layer 161 Electrical conductors 162 Particles 164 Substrate, material.

Claims

1. Device (10; 100; 150) for determining the implantation of a single particle (42a, 42b, 42c, 42d; 114, 116; 162) from a particle source (40; 152) into a material (12; 102; 164), wherein the device (10; 100; 150) comprises the particle source (40; 152) and the material (12; 102; 164), characterized in that the device further has a first layer (14; 104; 160), wherein the first layer (14; 104; 160) comprises one of the substances from the group: graphite, graphene, bismuth, zinc telluride, silver selenide, and mercury telluride, and is arranged between particle source (40; 152) and material (12; 102; 164), wherein the first layer (14; 104; 160) changes its resistance when the single particle (42a; 114; 162) penetrates the first layer (14; 104; 160), wherein the first layer (14; 104; 160) is a layer whose electrical resistance changes, relative to an undisturbed state, as compared with a state having an atomic lattice defect, wherein the device (10; 100; 150) moreover comprises means (16, 18; 106; 161) for determining the change in resistance of the first layer (14; 104; 160), and an evaluation unit (50), which monitors the electrical change in resistance of the first layer (14; 104; 160) and correlates it with a penetration of the first layer (14; 104; 160) by a single particle (42a, 42b, 42c, 42d; 114, 116; 162).

2. Device (10; 100; 150) according to claim 1, characterized in that the first layer (14; 104; 160) differs in its chemical composition from the material (12; 102; 164), and / or in that the first layer (14; 104; 160) is arranged spaced apart from the material (12; 102; 164), wherein an electrically insulating layer is preferably arranged between the material and the first layer, and / or in that the first layer (14; 104; 160) is configured in such a way that its ohmic resistance changes permanently after the particle has passed through it, preferably by destruction of its lattice structure, and / or in that the first layer (14; 104; 160) is arranged on the material (12; 102; 164), and / or in that the first layer (14; 104; 160) is configured as a grid structure, and / or in that the first layer (14; 104; 160) is a layer (14; 104; 160) that has semiconductor properties and at room temperature has a small energy gap and a very low conduction-electron density, and / or in that the first layer (14; 104; 160) has a thickness in the range from 5 nm to 100 nm, preferably in the range from 15 nm to 25 nm.

3. Device (10; 100; 150) according to claim 1 or 2, characterized in that the first layer (14; 104; 160) is configured in island-shaped form, wherein the islands (14; 104; 160) are connected via electrical lines (16, 18; 106; 161), wherein the islands (14; 104; 160) preferably have a larger dimension than the lines (16, 18; 106; 161) and / or consist of the same substance as the islands.

4. Device (10; 100; 150) according to claim 3, characterized in that the islands (14; 104; 160) have a dimension in the range from 1 nm × 1 nm to 500 nm × 500 nm, preferably a dimension in the range from 10 nm × 10 nm to 100 nm × 100 nm, more preferably a dimension in the range from 15 nm × 15 nm to 50 nm × 50 nm, more preferably a dimension in the range from 20 nm × 20 nm to 30 nm × 30 nm, and / or in that the islands (14; 104; 160) have a spacing from one another in the range from 10 nm to 500 nm, preferably in the range from 20 nm to 100 nm, in particular in the range from 40 nm to 60 nm.

5. Device (100) according to one of the preceding claims, characterized in that at least one electrode (110) is present, which is preferably arranged on the side of the first layer (104) opposite the material (102).

6. Device (150) according to one of the preceding claims, characterized in that the particle source (152) is arranged movably relative to the material (12; 102; 164), and / or in that the particle source (152) has an aperture (158) that is present on an AFM cantilever (156).

7. Device (10; 100; 150) according to one of the preceding claims, characterized in that on the side of the first layer (14; 104) opposite the material (12; 102; 164), at least one mask (22, 28; 108) is arranged that is impenetrable to the particle at selected kinetic energies, wherein the mask (22, 28; 108) preferably at least partially covers the first layer (14; 104), and wherein the mask (22, 28; 108) in particular has at least one opening (26; 112) that defines a channel for passing the particle (42a; 114) through the mask (22, 28; 108).

8. Device (10; 100; 150) according to claim 7, characterized in that the opening (30) of the mask (22, 28; 112) is less than or equal to 100 nm, preferably less than or equal to 50 nm, more preferably less than or equal to 10 nm, in particular less than or equal to 5 nm.

9. Device (10) according to one of the preceding claims, characterized in that on the side of the first layer (14) opposite the material (12), at least one second layer (24) is arranged that can be melted by heating and is impenetrable to the particle (42d) at selected kinetic energies.

10. Device (10) according to claim 9, characterized in that a heating element (14) for heating the second layer (24) is present, wherein the heating element is preferably formed by the first layer (14).

11. Device (10) according to one of claims 7 or 8 in combination with one of claims 9 or 10, characterized in that the second layer (24) is present adjoining the mask (28), wherein the second layer (24) is preferably arranged between the material (12) and the mask (28), and wherein in particular it is provided that the second layer (24), in the unmelted state, does not cover openings (30) in the mask (28).

12. Device (10; 100; 150) according to one of claims 7 to 11, characterized in that the mask (22, 28) comprises a thermoplastic, preferably PMMA, and / or in that the second layer (24) comprises one of the substances from the group: wax and polymer, wherein the polymer is preferably polycaprolactone (PCL), and / or in that the second layer (24) has a melting point of less than or equal to 100 °C.

13. Method for determining the implantation of a single particle (42a, 42b, 42c, 42d; 114, 116; 162) from a particle source (40; 152) into a material (12; 102; 164), characterized in that between particle source (40; 152) and material (12; 102; 164) a first layer (14; 104; 160) is arranged, which comprises one of the substances from the group: graphite, graphene, bismuth, zinc telluride, silver selenide, and mercury telluride, and which changes its resistance when the particle (42a; 114; 162) penetrates the first layer (14; 104; 160), wherein the first layer (14; 104; 160) is a layer whose electrical resistance changes, relative to an undisturbed state, as compared with a state having an atomic lattice defect, wherein the change in resistance of the first layer (14; 104; 160) is determined and is correlated with a penetration of the first layer (14; 104; 160) by a single particle (42a, 42b, 42c, 42d; 114, 116; 162).

14. Method according to claim 13, characterized in that the device (10; 100; 150) according to one of claims 1 to 12 is used, and / or in that the material (12; 102; 164) is kept in vacuum, wherein the maximum pressure is preferably less than or equal to 0.0001 mbar, and / or in that the material (12; 102; 164) comprises one of the substances from the group: diamond, SiC, silicon, TiO2, and ZnO.

15. Method according to one of claims 13 or 14, characterized in that the method is used for deterministic ion implantation, preferably for producing quantum systems, and / or in that the method is used for spatially resolved single-particle detection, and / or in that the method is used for spatially resolved mass spectrometry, and / or in that the method is used for ion-beam-assisted materials research, and / or in that the method is used for producing certain magnetic moments in the material (12; 102; 164).

16. Use of the device (10; 100; 150) according to one of claims 1 to 12 for producing a detector for mass spectrometry, a detector for single-particle implantation, an information store, or a component for a quantum computer, preferably a processor for a quantum computer.