DE102014107458B4 - patterning methods - Google Patents

Abstract

Structuring method for producing a spatially periodic surface structuring, comprising the steps: - providing a substrate with a layer (1) to be structured from a single-crystalline layer material comprising at least two chemical elements, - heating the substrate with the layer (1) by means of contact heating (5) , and - irradiating a surface (9) of the heated layer (1) to be structured with an ion beam (7), producing lattice defects in the form of vacancies in the layer (1).

Description

The invention relates to a structuring method, in particular a structuring method for producing spatially periodic surface structuring, which have structural elements with dimensions in the nanometer range.

Nanostructured arrangements or workpieces are used in a wide variety of technical areas and can be manufactured using different processes. So it is e.g. known in the semiconductor industry to produce structures with dimensions in the nanometer range using lithographic masks by means of photolithographic or electron beam lithographic methods. In optical lithography, the resolution is limited by the wavelength of the light used, so that these methods are very complex for small structural dimensions. Electron beam lithography, in turn, is very time consuming due to the serial nature of this process. These processes are therefore only conditionally suitable for structuring large areas for mass production.

As another example, describes the DE 199 32 880 A1 a method for producing regular semiconductor structures with dimensions in the nanometer range by means of ion sputtering, wherein a substrate from a compound semiconductor with two components is bombarded with noble gas ions, with a surface structuring taking place due to different sputtering rates of the two components. The substrate is cooled during the ion bombardment, for example by means of water or by means of liquid nitrogen. The resulting structures are distributed relatively evenly over the structured surface, but the order is not completely regular and is limited to a short-range radius of a few 100 nm, so that this method is not suitable for producing high-quality periodic structures. In addition, the structuring is accompanied by destruction of the crystal structure, at least on the surface of the structures produced, so that this method is not suitable for producing continuously crystalline workpieces or structures of high crystalline quality.

The poor regularity and crystalline quality, however, have an adverse effect in many areas and limit the potential applications of these structural arrangements. For example, the electrical transport properties of nanowires are greatly affected by the amorphous surface areas.

The DE 10 2009 046 756 A1 describes on the basis of the method according to DE 199 32 880 A1 a process for the production of regular nanostructures on a solid surface, but first a relief with a structuring in the submicrometer range is applied to the solid surface and then ion radiation is carried out while removing the relief and structuring the underlying solid surface.

In “Composition and structure of ion-bombardment-induced growth cones on InP” (JB Malherbe, H. Lakner, WH Gries in: Surface and Interface Analysis, Vol. 17, 719 - 725, September 1991) the formation of surface structures is described Irregularly arranged, cone-shaped elevations (so-called "cones") treated by ion irradiation from InP.

The invention provides an uncomplicated and cost-effective method for producing large-area, spatially periodic surface structuring or surface profiles with periodically arranged structural elements, the structural elements also having a high crystalline quality. For this purpose, a method is provided with the features according to claim 1, embodiments of the method result from the dependent claims.

According to the invention, a structuring method for producing a component with a spatially periodic surface structuring is provided, the structural elements of the surface structuring having dimensions in the nanometer range. In other words, a structuring method for producing a nanostructured arrangement with periodically arranged structural elements is thus provided. According to the structuring method, a substrate is first provided which has a layer to be structured from a single-crystalline layer material or consists of at least two chemical elements. Accordingly, the layer consists of a single crystal of a compound with at least two chemical elements as components, for example of single crystal GaAs or InAs. The substrate with the single-crystalline layer is heated, the substrate being heated by means of a contact heater. A surface of the heated layer to be structured is irradiated with an ion beam, the ion beam parameters (in particular the kinetic energy of the ions of the ion beam) being set such that lattice defects in the form of vacancies are generated by the ion beam in the single-crystal layer. The temperature of the substrate (and the layer) that is present during the structuring is also referred to below as the “structuring temperature”. The structuring temperature can be achieved using a temperature sensor (eg in the form of a thermocouple or Pyrometers) are recorded and regulated to a predetermined value.

It has surprisingly been found that the method according to the invention results in the production of faceted periodic surface structuring with high crystalline quality. In particular, the ion-based structuring method according to the invention with heating the layer to be structured compared to known ion-based structuring methods without heating or with cooling the layer to be structured enables the production of more regular surface structures, in particular the production of large-area periodic surface structures or surface reliefs. In the known methods without heating, the structuring takes place on a surface which is amorphized due to the ion irradiation and has a high defect density, as a result of which the structuring that is created has an irregular arrangement of its structural elements and a high density of topographic defects.

The structuring method according to the invention is based on a self-organizing process which is based on the diffusion of the created vacancies, the structuring resulting in a faceted surface (i.e. the surface structure has or consists of a plurality of flat partial surfaces which are tilted relative to one another). The self-organizing process is driven by the minimization of the total energy, whereby the faceting corresponds to the nanostructuring of the surface structure with the lowest energy, which is kinetically accessible at the structuring temperature during the ion irradiation. The invention thus provides an uncomplicated structuring method suitable for mass production. The invention also relates to the use of the structuring methods described for producing components with such faceted periodic surface structuring.

By heating the layer to be structured during the structuring, the ion-induced defects can thermally heal during the structuring or during the ion irradiation with at least partial recrystallization of the layer material, whereby in particular the amorphization of the layer regions near the surface can be reduced or even prevented, so that spatially periodic surface structuring results from the periodicity of the structured material. By thermally healing the ion-induced crystal defects, the resulting structured arrangement can be formed with a high crystalline quality. The substrate is preferably heated in such a way that the substrate temperature during ion irradiation is at least as high as the recrystallization temperature of the layer material, since above the recrystallization temperature a particularly effective recrystallization and healing of the defects is made possible.

The ion beam is preferably a homogeneous ion beam with an ion current density and ion energy that is homogeneous over the cross section of the ion beam. The surface of the layer to be structured, on which the structuring takes place, is preferably a flat surface, e.g. a crystal plane. The ion beam can either be stationary or guided over the surface to be structured, but - in contrast to e.g. mask-based method - the entire surface to be structured of the layer is exposed to the same ion irradiation (ie the ion irradiation is independent of location over the entire area to be structured, with each section of the surface to be structured being subjected to the same ion irradiation with the same irradiation parameters as kinetic ion energy, ion current density or ion flux density, irradiation duration , resulting ion fluence etc. is exposed). Accordingly, it is preferably provided that the ion beam is a homogeneous ion beam with an ion current density and ion energy that is homogeneous over the cross section of the ion beam, the ion beam being shaped and guided such that the cross section of the ion beam is at least as large as it strikes the layer to be structured the surface to be structured and thus the ion beam covers at least the entire surface to be structured when it hits the layer.

The ion beam can consist of electrically charged ions or of (subsequently) neutralized ions. The ion beam is preferably a collimated ion beam which runs along a direction of propagation or radiation direction. The ion beam strikes the layer surface to be structured perpendicularly or at a different angle

The resulting surface structuring or nanostructured arrangements have periodically arranged structural elements of high crystalline quality. The resulting arrangement is nanostructured, i.e. has structural elements with dimensions of less than 1000 nm (although the structural elements need not exclusively have dimensions of less than 1000 nm). The term “nanostructured” here refers to structuring with structure dimensions in the nanometer range, i.e. of less than 1000 nm.

The method according to the invention is based on a self-organizing process in the ion irradiation of a single-crystalline and thus pure layer with the formation of vacancies or vacancies and is to be distinguished in particular from Structuring processes that are based on the shadowing of ion radiation by foreign materials or defects in a material to be structured. Such shadowing-based processes usually result in surface structuring with irregularly arranged, conical elevations (so-called "cones") or depressions (so-called "pits").

The shape and the alignment of the resulting structuring is determined by the crystal symmetry of the ion-irradiated layer surface, the resulting structural elements being aligned along the crystallographic directions of the crystal lattice of the layer to be structured. For example, with ion irradiation of a (100) plane on GaAs or another single crystal with a zinc diaphragm crystal structure, a periodic wave profile with wave fronts running along the [1-10] direction. The dimensions of the structural elements of the arrangement depend on the ion energy, the ion current density, the ion fluence and the structuring temperature, the resulting structural elements having dimensions in the range from a few nanometers to a few hundred nanometers. Accordingly, the nanostructures produced can e.g. are in the form of checkerboard patterns or dot patterns and can in particular be in the form of wave profiles or line patterns with double symmetry. Such nanostructured arrangements or patterns can be used for the production of optical, electronic, optoelectronic, thermoelectric and photovoltaic devices, but also for energy storage, for catalysis, for chemical analysis, for photodetectors and for other sensors.

The method can be used in particular to produce periodic line patterns or wave profiles with structural dimensions in the nanometer range, which e.g. can be used as an optical grating, for the production of nanowires, as a nanostructured template for (e.g. epitaxial) growth of further materials or for forming the channel area of a field effect transistor. The structuring method can thus be used in particular for the production of an optical grating, for the production of nanowires, and for the production of deposition templates for the deposition of foreign materials thereon (e.g. epitaxy templates for the deposition of foreign materials by means of epitaxy). In the production of an optical line grating and a deposition template, the nanostructured component produced can be used directly as such a line grating or deposition template; so that the structuring method provides a method for producing an optical grating or deposition template.

The method does not require any special pretreatment of the surface to be structured, since the surface is subject to constant cleaning due to the ion radiation.

According to one embodiment, the ion beam parameters (in particular the kinetic energy of the ions of the ion beam) are set such that the ion beam on the surface of the heated layer removes material by means of sputtering. Sputtering or ion sputtering means the removal of atoms from a solid by bombarding the solid with ions. The material removal can additionally support the vacancy-driven structure formation, since proportionately more vacancies than adatoms are generated during sputtering.

The layer to be structured consists of a single-crystalline layer material with two or more chemical elements in any stoichiometry. According to one embodiment, the layer material is a compound semiconductor, in particular a III-V compound semiconductor such as, for example, GaAs, InAs or GaSb. However, it can also be provided that the layer material is a II-VI compound semiconductor, for example ZnSe, CdTe or HgS, or else a semiconductor composed of two elements of the fourth group of the periodic table, for example SiC or SiGe. The layer material can also be an oxide (for example TiO ₂ , ZnO) or an intermetallic compound (for example GaPd, FeAl, MgSi ₂ ).

The ion beam can consist of any ions, preferably ions of an inert gas (approximately N ⁺ ), for example ions of a noble gas (such as He ⁺ , Ne ⁺ , Ar ⁺ , Kr ⁺ or Xe ⁺ ). The structuring or ion irradiation of the substrate is carried out under vacuum, for example in a vacuum chamber (wherein, for example, pressures of below 10 ^-3 mbar are present during the structuring). The ions of the ion beam preferably have a kinetic energy between 50 eV and 10 keV. The ion beam preferably has an ion current density or ion flux density of at most 10 ¹⁷ cm ^-2 s ^-1 , in particular between 10 ¹⁴ cm ^-2 s ^-1 and 10 ¹⁷ cm ^-2 s ^-1 ; the ion fluence preferably has a value between 10 ¹⁶ cm ^-2 and 10 ²⁰ cm ^-2 . The irradiation time is typically in the range between 60 min and 120 min, but depends on the specific process conditions.

The ion beam can be formed with a large cross section, so that structuring over a large area is made possible in a single step, the method according to the invention being able to be carried out in particular over a large area without beam-shaping masks due to the self-organizing structuring process. In contrast to, for example, mask-based methods, it can in particular be provided that the ion beam is such is formed and shaped that the smallest cross-sectional dimension of the ion beam is larger than the smallest structure size of the structuring to be produced at the location of the impact of the ion beam on the layer. For example, it can be provided that the smallest cross-sectional dimension of the ion beam is at least 1000 nm or more (for example at least 1 mm, 1 cm or 10 cm) at the point of impact with the layer. Furthermore, the ion beam can be designed in such a way that it has a cross-sectional dimension that is greater than the period length of the periodic structuring to be produced along the periodicity of the periodic arrangement or structuring to be imposed on the layer. In particular, it can be provided that the cross section of the ion beam impinging on the layer to be structured covers the entire area of the single-crystalline layer to be structured, for example covering the entire layer to be structured or its front side.

Ion defects produce crystal defects in the layer to be structured, e.g. Vacancies, interstitials and Frenkel defects. According to the current state of knowledge - especially if the structuring temperature corresponds at least to the recrystallization temperature of the layer material - ion-induced vacancies and interstitial atoms inside or in the bulk material of the layer can heal thermally, so that only adatoms and vacancies remain in a section of the layer near the surface. Accordingly, the surface nanostructuring results primarily from the kinetics of the ion-induced vacancies and adatoms, due to their more frequent occurrence the kinetics of the vacancies are regarded as crucial and the structuring is strongly dependent on the diffusion and distribution of the vacancies near the surface.

The kinetic energy of the ions of the ion beam is so high that lattice defects in the form of vacancies are generated by the ions in the layer. According to one embodiment, the layer is heated to such a high temperature that at least some of the vacancies generated can diffuse to the irradiated surface of the layer during the duration of the irradiation with the ion beam. Vacancies are thus generated by the ion beam at a predetermined penetration depth, the vacancies in the layer material having a temperature-dependent diffusion constant which increases with increasing temperature. According to this embodiment, vacancies generated in the interior of the layer can diffuse onto the irradiated surface of the layer, as a result of which the regularity and the crystal quality of the resulting structure are additionally improved, so that the resulting structures can in particular also be completely crystalline on the surface.

According to a further embodiment, the structuring temperature is at most as high as the temperature corresponding to the Ehrlich-Schwoebel barrier of the layer material, the temperature of the Ehrlich-Schwoebel energy barrier E _ES corresponding temperature or activation temperature T _ES can be determined according to E _ES = kT _ES (where k denotes the Boltzmann constant). Accordingly, the structuring temperature is at most as high as the temperature at which the thermal energy of the atoms of the layer material is as large as the Ehrlich-Schwoebel barrier of the layer material and above which the Ehrlich-Schwoebel barrier thus becomes inactive.

For the diffusion of vacancies or atoms on a crystal surface, there is an activation barrier at a crystal stage due to the reduction in the coordination number associated with the stage position, which is known as an Ehrlich-Schwoebel barrier (also known as “ES barrier” for short). Since the surface of the layer to be structured remains essentially crystalline during the ion irradiation, the diffusion of the vacancies and adatoms on their surface is influenced by the ES barrier, especially as long as the thermal energy of the diffusing defects (in particular vacancies) does not overcome the ES - Barrier is sufficient. Since the structuring temperature is at most as high as the temperature corresponding to the Ehrlich-Schwoebele barrier of the layer material (in particular for the diffusion of vacancies and / or adatoms) above which the ES barrier becomes inactive, the structuring can be Barrier are supported.

The structuring temperature can be between 30 ° C and 1000 ° C depending on the layer material. The determination of the above conditions for the structuring temperature can be complex in practice, especially since other factors may have to be taken into account for the optimal structuring temperature. It has been shown - in particular for compound semiconductors as layer materials - that if the structuring temperature is set to a value between 25% and 75% of the absolute (ie measured in Kelvin) melting temperature of the layer material, surface structuring can be produced with a high degree of regularity and a high crystal quality, so that, according to one embodiment, the structuring temperature lies within this temperature window. In particular, a value of 40% of the absolute melting temperature can be used as an estimate for the recrystallization temperature. For example, when irradiated with Ar ⁺ ions, an ion energy of 1 keV for InAs as layer material in a temperature window from 100 ° C to 430 ° C and for GaAs as layer material in a temperature window from 200 ° C to 500 ° C good structuring results with high periodicity and crystalline quality can be achieved.

Although ion radiation already introduces heat into the layer to be structured, the substrate with the layer to be structured is preferably heated in addition to the ion-induced heat input. This enables a particularly effective healing of the lattice defects caused by the ions. An increase in the ion-induced heat input is always accompanied by an increase in the ion-induced lattice defects, which has a negative effect on the crystal quality. In contrast to this, the structuring temperature can be set independently of the ion radiation by means of an additional ion-independent heating.

The layer to be structured has a front side provided for structuring and a rear side facing away from the same, the ion beam being directed onto the front side of the layer. According to one embodiment, the layer to be structured is heated from the rear. For example, it may be provided that the substrate (which has the layer) for heating is in contact with a contact element or temperature control element (e.g. a heating plate) of a heating device.

The temperature control element in contact with the substrate preferably consists of a non-metallic material, e.g. made of a semiconductor material. As a result, the diffusion of metallic impurities, which usually have high diffusion speeds, into the layer to be structured can be prevented. This is particularly relevant in the production of crystalline semiconductor structures from a layer of a compound semiconductor as the layer material, since metallic impurities can considerably impair the electrical and crystalline properties of the compound semiconductor.

It can also be provided that the temperature control element consists of the same material as the layer to be structured, whereby a disturbance of the crystal structure of the layer by foreign materials that diffuse in is reliably prevented.

In accordance with one embodiment, the layer material is a material which has the zinc diaphragm structure as a crystal structure. For example, many compound semiconductors have this crystal structure. When structuring at (100) planes of such a layer material, a surface structuring with a four-fold or two-fold symmetry is expected, whereas when structuring at (111) planes a six-fold or three-fold symmetry is to be expected. Accordingly, surface structuring with different shapes can be produced by structuring on surfaces with different crystal orientations.

In particular, it can be provided that the layer is formed in such a way that the layer surface to be structured is a (100) plane of the zincblende crystal structure (i.e. that the front side of the layer provided for structuring corresponds to a (100) crystal plane). In this case, periodic wave profiles or dashed grids can be generated using the structuring method, the surface structuring generated in this way e.g. can be used as an optical grating or as a template for (e.g. epitaxial) growth of another material. In the case of ion irradiation of a (100) plane under perpendicular beam incidence, the resulting line grating is formed symmetrically in such a way that both flanks of a “line” or web of the grating have the same angle with respect to the surface normal of the (100) plane.

According to one embodiment, the irradiated surface or the front side of the layer to be structured is a flat surface which has a mismatch with respect to a (100) plane of the zincblende crystal structure. In the case of ion irradiation of such a faulty cut surface - in particular under normal incidence or perpendicular incidence of the ion beam - the resulting line grating is designed asymmetrically such that the two flanks of a line or web of such a line grating have different angles with respect to the surface normal of the irradiated faulty cut surface. Such an asymmetrical grating can e.g. can be used as a blaze grid or as an orientation-selective coating (e.g. by vapor deposition), so that the invention also provides methods for producing a blaze grid and an orientation-selective deposition template. The blaze angle of such a blaze grid can be adjusted by adjusting the incorrect cut or the incorrect cut angle (angle between the (100) plane and the surface plane to be structured). The mis-cut angle with respect to the (100) plane is preferably up to 30 °, e.g. towards the (111) plane.

• 1 eine schematische Illustration eines Strukturierungsverfahrens gemäß einer Ausführungsform;
• 2 eine Rasterelektronenmikroskopie-Aufnahme einer strukturierten (100)-Oberfläche einer GaAs-Schicht in Draufsicht;
• 3 eine Rasterelektronenmikroskopie-Aufnahme einer strukturierten (100)-Oberfläche einer InAs-Schicht in Draufsicht;
• 4 eine Transmissionselektronenmikroskopie-Aufnahme einer strukturierten GaAs-Schicht im Querschnitt;
• 5 eine schematische Darstellung zur Veranschaulichung der Herstellung eines periodischen Wellenprofils mit asymmetrischen Flanken;
• 6 eine schematische Darstellung zur Verwendung des gemäß 5 hergestellten Bauelements als Abscheidungs-Template; und
• 7 eine schematische Darstellung zur Veranschaulichung eines Verfahrens zum Herstellen von Nanodrähten.

The invention is explained below using exemplary embodiments with reference to the accompanying figures, the same or similar features being provided with the same reference numerals. The figures show:

• 1 a schematic illustration of a structuring method according to an embodiment;
• 2 a scanning electron microscope image of a structured (100) surface of a GaAs layer in plan view;
• 3 a scanning electron micrograph of a structured (100) surface of an InAs layer in plan view;
• 4 a transmission electron microscope image of a structured GaAs layer in cross section;
• 5 a schematic representation to illustrate the production of a periodic wave profile with asymmetrical flanks;
• 6 is a schematic representation of the use of the 5 manufactured component as a deposition template; and
• 7 a schematic representation to illustrate a method for producing nanowires.

1 illustrates a structuring method according to an embodiment. According to 1 becomes a substrate 1 provided, the substrate 1 as an example completely from one layer 1 of a single-crystal material consists of two chemical elements. The substrate 1 is, for example, a circular wafer of a III-V compound semiconductor, for example GaAs or InAs, with a diameter of 1 cm. The substrate 1 is in a vacuum chamber 3 in contact with a temperature control element 5 a heating device, not shown, arranged, the substrate 1 during the structuring process using the temperature control element 5 the heater is heated. An ion beam 7 an ion source (not shown) (eg a Kaufman ion source) becomes the flat front 9 of the substrate directed. The ion beam 7 is a collimated, homogeneous ion beam from ions of a noble gas (here: Ar ⁺ ions) with a kinetic energy between 50 eV and 10 keV, the kinetic energy in the present example being 1 keV. The ion current density here is 10 ¹⁶ cm ^-2 s ^-1 with an ion fluence of 10 ¹⁹ cm ^-2 . The ion beam 7 has a circular cross section with a diameter of more than 1 cm, so that from it the entire front 9 of the substrate 1 is covered and thus the entire surface to be structured 9 exposed to the same ion radiation (ie the substrate 1 over the entire front 9 exposed to the same ion radiation). The ion beam 7 strikes the surface to be structured at a right angle 9 the front of the substrate 1 , whereby material is removed by means of sputtering while creating empty spaces. In the 1 The illustrated structuring device can also include a mass spectrometer for identifying the sputtered elements and a pyrometer for contactless detection of the temperature of the substrate 1 have (not shown).

If the substrate 1 consists of GaAs as layer material, the substrate 1 by means of the temperature control element 5 heated to a temperature in the range between 200 ° C and 500 ° C during the ion irradiation, in this case as an example to 400 ° C (which corresponds to approx. 45% of the absolute melting temperature of GaAs). If the substrate 1 consists of InAs as layer material, the substrate 1 by means of the temperature control element 5 heated during the ion irradiation to a temperature in the range between 100 ° C and 430 ° C, in the present case as an example to 350 ° C (which corresponds to approx. 50% of the absolute melting temperature of GaAs).

During structuring or during ion radiation, the pressure in the vacuum chamber is less than 10 ^-3 mbar. The temperature control element 5 consists of boron nitride as a non-metallic material.

Under the radiation conditions mentioned, a self-organizing, large-area structuring of the surface takes place with material removal 9 of the substrate 1 forming a faceted, crystalline and periodic surface structure, the shape of the structural elements and the symmetry of the resulting surface structuring of the crystal structure and crystal orientation of the substrate 1 and depend on the radiation parameters.

2 shows a scanning electron micrograph of a (100) surface of a GaAs layer, which was structured by means of a method according to an embodiment, in plan view. Accordingly, a GaAs substrate 1 having a (100) crystal plane as a front 9 provided and irradiated with perpendicular ion beam incidence under the ion conditions specified above, wherein the GaAs substrate was heated to a temperature of 400 ° C. As in 2 shown, the ion irradiation results in a periodic wave profile or line pattern with structure dimensions in the nanometer range, the wave fronts or lines running along the [1-10] crystal direction of the zinc diaphragm crystal lattice of the GaAs substrate 1.

3 shows a scanning electron micrograph of a (100) surface of an InAs layer, which was structured by means of a method according to an embodiment, in plan view. Accordingly, an InAs substrate 1 having a (100) crystal plane was used as the front 9 provided and irradiated with perpendicular ion beam incidence under the ion conditions specified above, wherein the InAs substrate was heated to a temperature of 350 ° C. As in 3 shown, the ion irradiation results in a periodic wave profile or line pattern with structure dimensions in the nanometer range, the wave fronts or lines running along the [1-10] crystal direction of the zincblende crystal lattice of the InAs substrate 1.

The structural elements or wave fronts of the periodic wave profiles according to 2 and 3 run along the [1-10] crystal direction, the period length of the wave profile can be set to a value between 30 nm and 500 nm and the amplitude of the wave profile can be set to a value between 5 nm and 200 nm by the ion energy, ion current density, ion fluence , Irradiation temperature and incorrect cut (the irradiated surface opposite the (100) plane) can be varied.

4 shows a transmission electron microscope image of a (100) surface of a GaAs layer, which was structured analogously to the procedure described above, in cross section. As can be seen, the structured surface has a faceted periodic structure with a high crystalline quality even in the surface area. The structuring was carried out by means of perpendicular ion beam incidence on the (100) plane. How from 4 can be seen, the structuring results in a wave profile or web pattern, the two flanks of a web of the web pattern each having the same angle (here: approx. 20 °) with respect to the (100) plane.

5 shows a schematic side view of the surface structuring that occurs when a layer 1 is structured from a layer material with a zincblende crystal structure according to one embodiment, the irradiated front side 9 the layer is a flat surface that is opposite a ( 100 ) Plane of the zincblende crystal structure a miscut (e.g. 10 ° in the direction of the ( 111 ) Level). For illustration, see 5 the orientation of the ( 100 ) Plane schematically using the dashed line 11 shown. The layer material can be, for example, InAs or GaAs, and the structuring can be carried out using the ion beam parameters and structuring temperatures described above for InAs or GaAs. If the ion beam 7 is incident perpendicularly on the faulty cut surface, the ion irradiation results in a wave profile or web pattern, the two flanks 13 . 15 of a web of the web pattern have different angles with respect to the surface normal of the irradiated false cut plane. The resulting surface-structured component can be used, for example, as a blaze grid or as an orientation-selective deposition template.

6 illustrates the use of the according 5 manufactured, surface-structured component 1 as a deposition template for growing foreign material 16 , for example by means of epitaxy or deposition.

7 illustrates a method according to an embodiment for producing nanowires or a nanowire arrangement (wherein a nanowire is understood to be a wire with a maximum cross-sectional dimension of 100 nm). According to 7 shows the substrate next to the single crystal layer 1 a second layer made of a material with two chemical elements 17 made of an electrically insulating material. The layer 1 has, for example, a zinc blende crystal structure (consists, for example, of a corresponding compound semiconductor), with the flat front side 9 the layer 1 corresponds to a (100) crystal plane. The structuring takes place when the ion beam 7 is incident perpendicularly on the front side 9 the layer 1 , As explained above, the structuring results in a wave profile ( 7b) , wherein the material removal by means of the ion beam until the insulating second layer is reached 17 is continued ( 7c ), whereby separated nanowires 19 result.

LIST OF REFERENCE NUMBERS

1

Layer of single-crystal material consisting of two chemical elements

3

vacuum chamber

5

Temperature control element of a heating device

7

ion beam

9

Front of the layer 1 / surface to be structured

11

(100) plane

13, 15

flank

16

foreign material to be grown

17

Layer of electrically insulating material

19

nanowire

Claims (10)

Structuring method for producing a spatially periodic surface structuring, comprising the steps: - providing a substrate with a layer (1) to be structured from a single-crystalline layer material comprising at least two chemical elements, - heating the substrate with the layer (1) by means of contact heating (5) , and - Irradiating a surface (9) to be structured of the heated layer (1) with an ion beam (7), producing lattice defects in the form of vacancies in the layer (1). Structuring procedure according to Claim 1 The surface (9) of the heated layer (1) is irradiated with material being removed from the heated layer (1) by means of sputtering by the ion beam (7). Structuring procedure according to Claim 1 or 2 The layer (1) is exposed to the same ion radiation over the entire surface (9) to be structured. Structuring procedure according to one of the Claims 1 to 3 , wherein the kinetic energy of the ions of the ion beam (7) is between 50 eV and 10 keV. Structuring procedure according to one of the Claims 1 to 4 The substrate is heated in such a way that the layer (1) has a temperature during irradiation with the ion beam (7) which is at least as high as the recrystallization temperature of the layer material. Structuring procedure according to one of the Claims 1 to 5 , wherein the substrate is heated such that the layer (1) has a temperature during the irradiation with the ion beam (7) which is at most as high as the activation temperature corresponding to the Ehrlich-Schwoebel barrier of the layer material. Structuring procedure according to one of the Claims 1 to 6 , wherein the layer material is a compound semiconductor. Structuring procedure according to one of the Claims 1 to 7 , wherein the layer material has the zinc diaphragm structure as a crystal structure. Structuring procedure according to Claim 8 , wherein the irradiated surface (9) of the layer (1) is a flat surface which has a false cut with respect to a (100) plane of the zincblende crystal structure. Using the structuring method according to one of the Claims 1 to 9 for producing a periodically nanostructured component with a faceted surface.

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