阅读说明：本技术 一种有序手性分子链制备方法及SiC器件衬底 (Ordered chiral molecular chain preparation method and SiC device substrate ) 是由 卢慧 王昊霖 皮孝东 于 2021-08-04 设计创作，主要内容包括：本发明提拱了一种有序手性分子链制备方法及SiC器件衬底,包括如下步骤：清洗SiC单晶衬底,以去除所述SiC单晶衬底表面杂质；将SiC单晶衬底置于真空度为1.0×10～(-10)mbar～3.0×10～(-10)mbar的制备腔内,通过直流加热方式对SiC单晶衬底进行加热除气；随后将SiC单晶衬底在900℃和1400℃下循环加热90min；然后切断直流加热,使SiC单晶衬底温度降至室温,从而使SiC单晶衬底表面均匀地形成有双层石墨烯；向制备腔内热蒸发2,2’-二苯乙炔基-4,4’-二溴联苯分子,使其在低温的SiC单晶衬底的双层石墨烯表面进行手性分离与自组装,当制备腔内真空度上升至1.0×10～(-9)mbar～3.0×10～(-9)mbar时,开始沉积分子,沉积一段时间分子后,可以制得大面积有序手性分子链。(The invention provides a preparation method of an ordered chiral molecular chain and a SiC device substrate, which comprises the following steps: cleaning the SiC single crystal substrate to remove impurities on the surface of the SiC single crystal substrate; placing the SiC single crystal substrate in a vacuum degree of 1.0X 10 ‑10 mbar～3.0×10 ‑10 In a mbar preparation cavity, the SiC single crystal substrate is heated and removed in a direct current heating modeGas; then circularly heating the SiC single crystal substrate at 900 ℃ and 1400 ℃ for 90 min; then cutting off direct current heating, and reducing the temperature of the SiC single crystal substrate to room temperature, so that double-layer graphene is uniformly formed on the surface of the SiC single crystal substrate; thermally evaporating 2,2 '-diphenylethynyl-4, 4' -dibromo biphenyl molecules into a preparation cavity, carrying out chiral separation and self-assembly on the surface of double-layer graphene of the low-temperature SiC single crystal substrate, and increasing the vacuum degree in the preparation cavity to 1.0 multiplied by 10 ‑9 mbar～3.0×10 ‑9 mbar, molecules are deposited, and after the molecules are deposited for a period of time, large-area ordered chiral molecular chains can be prepared.)

1. A method for preparing an ordered chiral molecular chain is characterized by comprising the following steps:

cleaning the SiC single crystal substrate, and removing impurities on the surface of the SiC single crystal substrate;

heating and degassing the SiC single crystal substrate in a direct current heating mode; then circularly heating the SiC single crystal substrate at 900 ℃ and 1400 ℃ for 90 min; then cutting off direct current heating, and cooling the SiC single crystal substrate to room temperature, so that double-layer graphene is uniformly formed on the surface of the SiC single crystal substrate;

placing the SiC single crystal substrate in a vacuum degree of 1.0X 10^-10mbar～3.0×10^-10A preparation cavity with mbar, wherein the temperature of the SiC single crystal substrate is lower than room temperature, 2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules are thermally evaporated in the preparation cavity to carry out chiral separation and self-assembly on the surface of double-layer graphene of the SiC single crystal substrate, and when the vacuum degree in the preparation cavity is increased to 1.0 multiplied by 10^-9mbar～3.0×10^-9And mbar, beginning to deposit molecules, and preparing a large-area ordered chiral molecular chain after the molecules are deposited for a period of time.

2. The method for preparing ordered chiral molecular chains according to claim 1, wherein the heating of the SiC single crystal substrate for 90min at 900 ℃ and 1400 ℃ is specifically: heating the SiC single crystal substrate at 900 ℃ for 15min, heating the SiC single crystal substrate to 1400 ℃ for 15min as the first heating, and repeating the steps until the third heating is finished.

3. The method according to claim 1, wherein the preparation chamber is an ultra-high vacuum preparation chamber of a scanning tunneling microscope.

4. The method for preparing the ordered chiral molecular chain according to claim 1, wherein the SiC single crystal substrate is heated to 600-650 ℃ and is continuously heated for 4-8 hours to perform heating degassing on the SiC single crystal substrate.

5. The method for preparing the ordered chiral molecular chain according to claim 1, wherein the thermal evaporation temperature of thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecule is 140-150 ℃, and the deposition time is 10-20 min.

6. The method for preparing an ordered chiral molecular chain according to claim 1, wherein the thermal evaporation temperature for thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 145 ℃, the temperature of the SiC single crystal substrate is lower than 0 ℃, and the deposition time is 10 min.

7. The method for preparing an ordered chiral molecular chain according to claim 1, wherein the thermal evaporation temperature for thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 143 ℃, the temperature of the SiC single crystal substrate is lower than 0 ℃, and the deposition time is 10 min.

8. The method for preparing an ordered chiral molecular chain according to claim 1, wherein the thermal evaporation temperature for thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 145 ℃, the temperature of the SiC single crystal substrate is lower than 0 ℃, and the deposition time is 15 min.

9. The method of claim 1, wherein the SiC single crystal is 4H-SiC (0001) or 6H-SiC (0001).

10. A SiC device substrate, comprising: the SiC single crystal substrate is uniformly formed with double-layer graphene and the ordered chiral molecular chains uniformly distributed on the surface of the double-layer graphene by the method for preparing the ordered chiral molecular chains according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of chiral molecule separation and preparation, in particular to a preparation method of an ordered chiral molecular chain based on 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl and a SiC device substrate.

Background

In the field of chemistry, there is a large class of molecules that exist as chiral isomers, which are left-handed and right-handed, but do not overlap, and which are referred to as "chiral molecules". For example, chiral molecules in some drugs have significant differences in biological activity, metabolic processes, toxicity, and the like, and some differences even have differences between "treatment" and "pathogenesis". In recent years, chiral separation has attracted much attention due to its application to thin film transistors, heterogeneous catalytic chemistry and pharmaceutical engineering, and therefore, how to separate the "left and right hands" of chiral molecules more economically, efficiently and conveniently has become an important issue.

In the prior art, chiral separation generally adopts methods such as crystallization resolution, chemical resolution, enzyme resolution, membrane resolution, extraction resolution, chromatographic resolution and the like, for example, the crystallization resolution is based on the formation of diastereomeric salts or covalent derivatives of enantiomers and pure chirality, separation is performed by utilizing the property difference of diastereomers, and then the derivatives are reduced to pure enantiomers. The chemical resolution method is that two enantiomers are converted into diastereoisomers by a resolution reagent, and then the diastereoisomers are separated by utilizing the difference of physicochemical properties. The extraction resolution method is a method for resolution by utilizing the difference of affinity acting force or chemical action difference of an extracting agent with chirality and two enantiomers in prochiral molecules.

The above-mentioned chiral separation methods in the prior art have a number of disadvantages: for example, the crystallization resolution method has the disadvantages of time and labor consumption and large deviation from expectation, the chemical resolution method has the disadvantages of low yield, low product purity, few enantiomer types suitable for chiral resolution and the like, the enzyme resolution method has the disadvantages of limited enzyme preparation varieties and high preparation price, so the technical scheme has the disadvantages of complicated operation steps, poor separation effect, incapability of separating and preparing chiral molecular long chains and incapability of chiral separation under the condition that some chiral molecules are originally not chiral or are difficult to perform chiral separation in solution, the 2,2 ' -diphenylethynyl-4, 4 ' -dibromobiphenyl needs to be prepared in solution, the prepared 2,2 ' -diphenylethynyl-4, 4 ' -dibromobiphenyl has chiral isomers, and the 2,2 ' -diphenylethynyl-4, 4 ' -dibromobiphenyl refers to figure 1 and is 2,2 ' -diphenylethynyl-4, the chemical structural formula of two enantiomers of 4 ' -dibromobiphenyl molecule on a 2D plane, but the two enantiomers of the 2,2 ' -diphenylethynyl-4, 4 ' -dibromobiphenyl molecule are randomly mixed together in a solution and cannot form an ordered chiral long chain, and the 2,2 ' -diphenylethynyl-4, 4 ' -dibromobiphenyl molecule prepared by the existing method is difficult to perform chiral separation in the solution.

Disclosure of Invention

The invention provides a preparation method of an ordered chiral molecular chain and a SiC device substrate, aiming at overcoming the problems that in the prior art, two enantiomers of a 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecule are randomly mixed together in a solution and cannot form the ordered chiral long chain, and the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecule prepared by the existing method is difficult to carry out chiral separation in the solution.

In order to achieve the above object, an embodiment of the present invention provides a method for preparing an ordered chiral molecular chain, including: cleaning the SiC single crystal substrate, and removing impurities on the surface of the SiC single crystal substrate; heating and degassing the SiC single crystal substrate in a direct current heating mode; then circularly heating the SiC single crystal substrate at 900 ℃ and 1400 ℃ for 90 min; then cutting off direct current heating, and reducing the temperature of the SiC single crystal substrate to room temperature, so that double-layer graphene is uniformly formed on the surface of the SiC single crystal substrate; placing the SiC single crystal substrate in a vacuum degree of 1.0X 10^-10mbar～3.0×10^-10In a mbar preparation chamber, the temperature of the SiC single crystal substrate is lower than room temperatureThermally evaporating 2,2 '-diphenylethynyl-4, 4' -dibromo biphenyl molecules in the preparation cavity to perform chiral separation and self-assembly on the surface of double-layer graphene on the SiC single crystal substrate, and increasing the vacuum degree in the preparation cavity to 1.0 multiplied by 10^-9mbar～3.0×10^-9And mbar, beginning to deposit molecules, and preparing a large-area ordered chiral molecular chain after the molecules are deposited for a period of time.

Optionally, the heating the SiC single crystal substrate cyclically at 900 ℃ and 1400 ℃ for 90min specifically comprises: heating the SiC single crystal substrate at 900 ℃ for 15min, heating the SiC single crystal substrate to 1400 ℃ for 15min as the first heating, and repeating the steps until the third heating is finished.

Optionally, the preparation chamber is an ultrahigh vacuum preparation chamber of a scanning tunneling microscope.

Optionally, the SiC single crystal substrate is heated to 600-650 ℃, and heating is continued for 4-8 hours to carry out heating degassing on the SiC single crystal substrate.

Optionally, the thermal evaporation temperature of thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 140-150 ℃, and the deposition time is 10-20 min.

Optionally, the thermal evaporation temperature for thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 143 ℃, the temperature of the SiC single crystal substrate is lower than 0 ℃, and the deposition time is 15 min.

Optionally, the thermal evaporation temperature for thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 145 ℃, the temperature of the SiC single crystal substrate is lower than 0 ℃, and the deposition time is 10 min.

Optionally, the thermal evaporation temperature for thermally evaporating the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 145 ℃, the temperature of the SiC single crystal substrate is lower than 0 ℃, and the deposition time is 15min

Optionally, the SiC single crystal is a 4H-SiC (0001) or 6H-SiC (0001) single crystal.

An embodiment of the present invention further provides a SiC device substrate, including: the preparation method of the ordered chiral molecular chain is characterized in that the double-layer graphene and the ordered chiral molecular chains uniformly distributed on the surface of the double-layer graphene are uniformly formed on the surface of the SiC single crystal substrate.

In conclusion, the beneficial effects of the invention are as follows:

the embodiment of the invention provides a preparation method of an ordered chiral molecular chain and a SiC device substrate, which have excellent chiral separation effect on 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules, wherein uniform double-layer graphene is formed on the surface of a SiC single crystal substrate, then the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules are thermally evaporated to perform chiral separation and self-assembly on the surface of the double-layer graphene, and finally a large-area ordered chiral molecular chain is obtained on the surface of the double-layer graphene of the SiC single crystal substrate, so that the double-layer graphene on the surface of the SiC single crystal substrate is modified, and conditions are provided for preparing a corresponding SiC chiral device by using the SiC single crystal substrate with the modified double-layer graphene.

In addition, by changing parameters such as thermal evaporation temperature, reaction time, degassing temperature, degassing time and the like, ordered chiral molecular chains with different chain lengths and different densities can be obtained on the surface of the double-layer graphene of the SiC single crystal substrate, and the embodiment of the invention can well control parameters such as the average chain length, the average width, the coverage degree and the like of the finally generated ordered chiral molecular chains, thereby providing a simple and flexible solution for the subsequent large-scale preparation of SiC chiral devices with different characteristics.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1 shows the chemical structural formulas of two enantiomers of a 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecule on a 2D plane according to an embodiment of the present invention;

FIG. 2 shows the chemical structural formulas of two chiral molecular chains prepared by the embodiment of the present invention.

Detailed Description

The present invention will be described in further detail below with reference to specific examples in order to facilitate understanding by those skilled in the art.

The embodiment of the invention firstly provides a preparation method of an ordered chiral molecular chain, which is used for separating two enantiomers shown in figure 1 and preparing a corresponding chiral molecular long chain.

In a first embodiment of the present invention, a method for preparing an ordered chiral molecular chain comprises the following steps:

the method comprises the following steps: cleaning the SiC single crystal substrate to remove surface impurities, wherein the SiC single crystal can be selected from 4H-SiC (0001) or 6H-SiC (0001).

Specifically, cleaning the SiC single crystal substrate to remove surface impurities thereof may include the steps of: doping n-type nitrogen with a doping concentration of 1.3 × 10¹⁸cm^-32 x 12mm in size²The SiC single crystal substrate is firstly washed by deionized water, then ultrasonic treatment is respectively carried out in the deionized water and ethanol for 15min, then the SiC single crystal substrate is clamped out of the ethanol by tweezers, and then high-purity N is used₂And blow-drying the surface of the SiC single crystal substrate.

The size, doping concentration and doping type of the SiC single crystal substrate are only one example of the method for preparing the ordered chiral molecular chain provided by the embodiment of the present invention, and a person skilled in the art can select SiC single crystal substrates with different sizes, different doping concentrations and different doping types to prepare large-area ordered chiral molecular chains according to needs.

The first step of the embodiment of the invention is mainly to clean the SiC single crystal substrate before the SiC single crystal substrate is placed in the preparation cavity, and remove organic matters and other impurities adsorbed on the surface of the SiC single crystal substrate, so that the subsequent graphene growth is not influenced, and the subsequent generated ordered chiral molecules have higher purity.

Step two: placing the SiC single crystal substrate in a vacuum degree of 1.0X 10^-10mbar～3.0×10^-10In the mbar preparation cavity, heating and degassing are carried out on the SiC single crystal substrate in a direct current heating mode, in the embodiment, the heating and degassing temperature range is 600-650 ℃, and the heating and degassing time is 4-8 hours; then circularly heating the SiC single crystal substrate at 900 ℃ and 1400 ℃ for 90 min; then cutting off direct current heating, reducing the temperature of the SiC single crystal substrate to room temperature, thereby enabling the surface of the SiC single crystal substrate to uniformly form double-layer graphene,compared with single-layer graphene, the graphene has better flatness in space.

The preparation cavity can be an ultrahigh vacuum preparation cavity of a scanning tunnel microscope, the SiC single crystal substrate is required to be fixed on a direct current heating sample frame matched with a heating table of the ultrahigh vacuum preparation cavity of the scanning tunnel microscope, the Si surface is upward, the SiC single crystal substrate is placed in a rapid sample injection cavity connected with the ultrahigh vacuum preparation cavity, and then the rapid sample injection cavity is vacuumized to 5.0 x 10^-7And mbar, opening a valve between the rapid sample introduction cavity and the preparation cavity, conveying the SiC single crystal substrate to a direct current heating table in the ultrahigh vacuum preparation cavity of the scanning tunnel microscope, heating the ultrahigh vacuum preparation cavity to 600-650 ℃, heating for 4-8 hours, and degassing the SiC single crystal substrate.

The method comprises the following steps of circularly heating the SiC single crystal substrate at 900 ℃ and 1400 ℃ for 90 min: heating the SiC single crystal substrate at 900 ℃ for 15min, raising the temperature to 1400 ℃ and heating for 15min as the first heating, and repeating the steps until the third heating is finished. Through the cyclic heating step at 900 ℃ and 1400 ℃, the flatness of the double-layer graphene on the surface of the SiC single crystal substrate is increased, so that the subsequent chiral separation effect of the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is greatly improved, the separation difficulty of the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is greatly reduced, and the problem that the chiral separation of the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules in a solution cannot be carried out is solved.

When the ultrahigh vacuum preparation cavity of the scanning tunnel microscope is selected as the preparation cavity, after the direct current heating is cut off and the temperature of the SiC single crystal substrate is reduced to room temperature, the SiC single crystal substrate can be placed in an analysis cavity with the temperature of the scanning tunnel microscope of 77K, and the scanning tunnel microscope is used for confirming that the double-layer graphene appears on the surface of the SiC single crystal substrate, wherein the double-layer graphene is uniformly distributed on the whole SiC single crystal substrate.

The second step of the embodiment of the invention is mainly to uniformly distribute the double-layer graphene on the whole SiC single crystal substrate.

Step three:

placing the SiC single crystal substrate at a temperature lower than room temperature in a vacuum degree of 1.0 × 10^-10mbar～3.0×10^-10A preparation cavity with mbar; thermally evaporating 2,2 '-diphenylethynyl-4, 4' -dibromo biphenyl molecules into a preparation cavity to perform chiral separation and self-assembly on the surface of double-layer graphene of the SiC single crystal substrate, and increasing the vacuum degree in the preparation cavity to 1.0 multiplied by 10^-9mbar～3.0×10^-9And mbar, beginning to deposit molecules, and preparing a large-area ordered chiral molecular chain after the molecules are deposited for a period of time.

Referring to fig. 2, the chemical structural formulas of two chiral molecular chains prepared in the embodiment of the present invention are shown, which correspond to a levorotatory molecular chain formed by self-assembling a levorotatory enantiomer (L) and a dextrorotatory molecular chain formed by self-assembling a dextrorotatory enantiomer (R), respectively.

The SiC single crystal substrate of the double-layer graphene appearing on the surface can be moved to a sample table at room temperature in a preparation cavity from 77K of an analysis cavity of a scanning tunneling microscope, and then 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules are immediately evaporated into the preparation cavity through thermal evaporation and deposited on the surface of the low-temperature SiC single crystal substrate.

In the first embodiment of the present invention, the temperature of the SiC single crystal substrate is lower than 0 ℃, the thermal evaporation temperature for thermally evaporating 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules is 143 ℃, and when the degree of vacuum in the preparation chamber rises to 1.0 × 10^-9mbar～3.0×10^-9And (3) beginning to deposit molecules at mbar for 10min, and closing a molecular thermal evaporation power supply after the deposition is finished so as to finish the deposition process.

After the deposition process is finished, the SiC monocrystal substrate can be conveyed to an analysis cavity, and a low-temperature scanning tunnel microscope is used for observing, so that a levorotatory molecular chain formed by self-assembling a levorotatory enantiomer (L) and a dextrorotatory molecular chain formed by self-assembling a dextrorotatory enantiomer (R) can be observed to be uniformly and orderly arranged on the surface of the double-layer graphene.

In the first embodiment of the present invention, the chain lengths of the levorotatory molecular chain and the dextrorotatory molecular chain are distributed between 97nm and 105nm, the average chain length is 100nm, the widths of the chiral molecular chains are distributed between 1.9nm and 2.0nm, the average width is 1.95nm, and the density is 60%, wherein the density is the coverage density of the ordered chiral molecules on the surface of the double-layer graphene.

The second embodiment of the present invention is different from the first embodiment in that: the evaporation temperature in the third step was 145 ℃ and the deposition time was 10min, and the other steps and parameters were the same as those in the first embodiment of the present invention. In the second step, the double-layer graphene on the surface of the SiC single crystal substrate is confirmed by using a scanning tunneling microscope, and the temperature of an analysis cavity of the scanning tunneling microscope is 77K, so that the temperature of the SiC single crystal substrate can be always lower than room temperature and even lower than 283K, the chiral molecular chain prepared by the second embodiment of the invention has the length ranging from 153nm to 168nm, the average length of 160nm, the width of 1.9nm to 2.0nm, the average width of 1.95nm and the density of 68%.

In the second embodiment of the present invention, in order to prepare the ordered chiral chain molecules with longer average chain length and higher coverage density on the surface of the double-layer graphene than that in the first embodiment of the present invention, the evaporation temperature is correspondingly increased in the third step, which is more favorable for the separation and self-assembly of the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules to generate long chains.

The third embodiment of the present invention is different from the first and second embodiments in that: and step three, the evaporation temperature is 145 ℃, the deposition time is 15min, and other steps and parameters are the same as those of the first embodiment and the second embodiment of the invention. The chiral molecular chain prepared by the third embodiment of the invention has the length ranging from 195nm to 214nm, the average length of 200nm, the chiral molecular chain width ranging from 1.9nm to 2.0nm, the average width of 1.95nm, and the chiral molecular chain is uniformly distributed on the surface of the SiC monocrystal substrate, and the density is 75%.

In the third embodiment of the invention, in order to prepare the ordered chiral molecular chain with longer average chain length and higher coverage rate compared with the second embodiment of the invention, the deposition time is correspondingly increased in the third step, so that the 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecule is more beneficial to separation and self-assembly of the long chain on the SiC single crystal substrate.

According to the preparation method of the ordered chiral molecular chain provided by the embodiment of the invention, the ordered chiral molecular chains with different chain lengths and different densities are finally obtained on the surface of the double-layer graphene of the SiC single crystal substrate by adjusting degassing heating temperature, heating time, evaporation temperature, deposition time and the temperature of the SiC single crystal substrate, so that the parameters of the ordered chiral molecular chain, such as average chain length, average width and coverage, are better controlled.

In summary, the preparation method provided by the embodiment of the invention has a simple process, can prepare large-area ordered chiral molecular long chains on the surface of the SiC single crystal, greatly improves controllability, high efficiency, repeatability and high purity in the preparation process of corresponding chiral molecules, and makes it possible to prepare corresponding ordered chiral molecular chains through 2,2 '-diphenylethynyl-4, 4' -dibromobiphenyl molecules controllably, efficiently and at high purity and move to industrial application.

The embodiment of the invention also provides a SiC device substrate, which comprises a SiC single crystal substrate, wherein double-layer graphene and ordered chiral molecular chains uniformly distributed on the surface of the double-layer graphene are uniformly formed on the surface of the SiC single crystal substrate by the ordered chiral molecular chain preparation method, so that the double-layer graphene on the surface of the SiC single crystal substrate is modified, and conditions are provided for preparing a corresponding SiC chiral device by subsequently utilizing the SiC device substrate with the modified double-layer graphene.

The substrate of the SiC device provided by the embodiment of the invention has the double-layer graphene and the structure of the ordered chiral molecular chain on the double-layer graphene, and parameters such as the average chain length, the average width, the coverage degree and the like of the ordered chiral molecular chain can be adjusted by changing the preparation process parameters, so that a simple and flexible solution is provided for the subsequent large-scale preparation of SiC chiral devices with different characteristics.

Finally, it is to be noted that any modifications or equivalent substitutions of some or all of the features may be made by means of the structure of the device according to the invention and the technical solutions of the examples described, without departing from the corresponding technical solutions of the invention, and the obtained essence falls within the scope of the structure of the device according to the invention and the claims of the embodiments described.