A nano-geometric standard sample and its preparation method and application

Abstract

The present invention belongs to the field of nano-testing technology, and provides a nano-geometric quantity standard template and its preparation method and application. The nano-geometric quantity standard template of the present invention includes a substrate and a nano-periodic structure two-dimensional supramolecular film attached to the substrate, and the nano-periodic structure two-dimensional supramolecular film is self-assembled by 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane. The nano-geometric quantity standard template of the present invention has excellent precision. The present invention also provides a preparation method of the nano-geometric quantity standard template, and self-assembly is to prepare the nano-periodic structure two-dimensional supramolecular film from bottom to top, which can more accurately control the morphology, size and performance of the nanostructure from bottom to top, so that the nano-periodic structure two-dimensional supramolecular film has high precision and high performance; by regulating the conditions of self-assembly, it is possible to achieve modulation of the length, line width and duty cycle of the nano-geometric quantity structure.

Description

Technical Field

[0001] The present invention relates to the field of nanometer testing technology, and in particular to a nanometer geometric quantity standard sample and a preparation method and application thereof. Background Art

[0002] As integrated circuit process nodes continue to shrink, chip performance is increasingly affected by nano-geometric dimensions, putting forward new requirements for high precision and high stability in nano-measurement. Traditional nano-measurement technology is mainly laser interferometry, which measures the changes in interference fringes to infer the tiny displacement or length change of the measured object. In laser interferometry, due to the influence of various factors (such as errors in optical components, signal distortion, etc.), nonlinear errors may occur, affecting the accuracy and stability of the measurement. In addition, laser interferometry is sensitive to environmental conditions (such as temperature, humidity, vibration, etc.), and measurements need to be carried out under relatively stable environmental conditions. Appropriate measures must be taken to reduce the impact of environmental factors, and the maintenance cost is high. Therefore, laser interferometry does not have advantages in terms of measurement accuracy, stability, and measurement cost in nano-measurement.

[0003] In 2018, the International Bureau of Weights and Measures established a method for reproducing the silicon lattice constant as the SI unit of the meter. Nanoscale geometric standard samples can be traced not only to laser wavelengths but also to atomic-scale silicon lattice constants. This improves the accuracy of their values ​​and offers significant advantages in nanometrology traceability and calibration. Currently, the main methods for preparing nanoscale geometric standard samples include photolithography, electron beam lithography, and deposition and etching techniques. The precision of these nanoscale geometric standard samples remains to be further improved. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide a nanometer geometric quantity standard sample and its preparation method and application. The nanometer geometric quantity standard sample provided by the present invention has high precision.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a nano-geometric quantity standard sample, comprising a substrate and a nano-periodic structure two-dimensional supramolecular film attached to the substrate, wherein the nano-periodic structure two-dimensional supramolecular film is obtained by self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diisophthalic acid and 1,2-bis(4-pyridyl)ethane.

[0007] Preferably, the substrate is made of highly oriented pyrolysis graphite, gold or copper.

[0008] The present invention also provides a method for preparing the nano-geometric quantity standard sample described in the above technical solution, comprising the following steps:

[0009] providing a substrate;

[0010] 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane are self-assembled on the substrate to obtain the nano-geometric quantity standard sample.

[0011] Preferably, the self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate comprises the following steps: sequentially adding a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and a 1,2-bis(4-pyridyl)ethane solution dropwise onto the substrate for self-assembly.

[0012] Preferably, the self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate comprises the following steps: sequentially adding 1,2-bis(4-pyridyl)ethane solution and 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution to the substrate for self-assembly.

[0013] Preferably, the self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate comprises the following steps: dropwise adding a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid / 1,2-bis(4-pyridyl)ethane mixed solution on the substrate for self-assembly.

[0014] Preferably, in the mixed system formed by the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and the 1,2-bis(4-pyridyl)ethane solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane is 1 to 1.5:1, the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid is 0.0005 to 0.002 mol / mL, and the pH value is 6 to 7.5.

[0015] Preferably, in the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid / 1,2-bis(4-pyridyl)ethane mixed solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane is 1-1.5:1, the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid is 0.0005-0.002 mol / mL, and the pH value is 6-7.5.

[0016] Preferably, the substrate is mechanically peeled off before use.

[0017] The present invention also provides the use of the nano-geometric quantity standard sample described in the above technical solution or the nano-geometric quantity standard sample prepared by the preparation method described in the above technical solution in nano-measurement.

[0018] The invention provides a nano-geometric quantity standard sample.

[0019] The invention forms a nano-periodic structure two-dimensional supramolecular film on a substrate by self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane. The self-assembled nano-periodic structure two-dimensional supramolecular film has excellent precision.

[0020] The present invention also provides a method for preparing the nano-geometric standard template described in the above technical solution. Self-assembly is the bottom-up preparation of nano-periodic structure two-dimensional supramolecular film. The bottom-up process can more accurately control the morphology, size and performance of the nanostructure, so that the nano-periodic structure two-dimensional supramolecular film has high precision and high performance; by regulating the conditions of self-assembly, the length, line width and duty cycle of the nano-geometric structure can be modulated; in addition, the preparation method of the present invention obtains a cross-scale nano-geometric structure; in addition, the preparation method of the present invention has the advantages of simple operation, low cost and easy scale-up, and is suitable for large-scale production applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A flowchart of the first self-assembly provided by the present invention;

[0022] Figure 2 This is the nano-grid STM image of the nano-periodic structure two-dimensional supramolecular film obtained in Example 1;

[0023] In the figure, 1-substrate, 2-disordered two-dimensional supramolecular film, 3-nanometer periodic structure two-dimensional supramolecular film. DETAILED DESCRIPTION

[0024] The present invention provides a nano-geometric standard sample, comprising a substrate and a nano-periodic structure two-dimensional supramolecular film attached to the substrate, wherein the nano-periodic structure two-dimensional supramolecular film is obtained by self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane.

[0025] Unless otherwise specified, the raw materials used in the present invention are preferably commercially available products.

[0026] The nano-geometric quantity standard sample provided by the present invention includes a substrate, and the material of the substrate preferably includes highly oriented cracked graphite, gold or copper, and more preferably is highly oriented cracked graphite.

[0027] The nano-geometric standard template provided by the present invention includes a nano-periodic structure two-dimensional supramolecular film attached to the substrate, wherein the nano-periodic structure two-dimensional supramolecular film is self-assembled from 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane. In the present invention, the thickness of the nano-periodic structure two-dimensional supramolecular film is preferably 0.3 to 1 nm. In the present invention, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid to 1,2-bis(4-pyridyl)ethane in the nano-periodic structure two-dimensional supramolecular film is preferably 1 to 1.5:1, specifically preferably 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1.

[0028] In the present invention, the nanoperiodic structure two-dimensional supramolecular film is preferably attached to any surface of the substrate. In the present invention, the nanoperiodic structure two-dimensional supramolecular film is attached to any surface of the substrate, so that any position of the nanometer geometric quantity standard sample can be used without positioning.

[0029] In the present invention, the nanoperiodic structure of the two-dimensional supramolecular film preferably includes a nanowire structure or a nanogrid structure.

[0030] In the present invention, the two-dimensional supramolecular film with a nano-periodic structure preferably has a nano-geometric structure across a wide range of scales; the nano-geometric structure preferably includes step height, length, pitch and line width.

[0031] The invention forms a nano-periodic structure two-dimensional supramolecular film on a substrate by self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane. The self-assembled nano-periodic structure two-dimensional supramolecular film has excellent precision.

[0032] The present invention also provides a method for preparing the nano-geometric quantity standard sample described in the above technical solution, comprising the following steps:

[0033] providing a substrate;

[0034] 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane are self-assembled on the substrate to obtain the nano-geometric quantity standard sample.

[0035] The present invention provides a substrate. In the present invention, the material of the substrate is preferably consistent with the above-mentioned technical solution, and will not be repeated here. Before use, the substrate is preferably subjected to mechanical exfoliation, and the present invention does not specifically limit the parameters of the mechanical exfoliation.

[0036] After providing a substrate, the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane of the present invention are self-assembled on the substrate to obtain the nano-geometric quantity standard sample.

[0037] In the present invention, the self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate preferably includes the following steps: sequentially adding a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and a 1,2-bis(4-pyridyl)ethane solution dropwise onto the substrate to perform self-assembly (referred to as the first self-assembly). In the present invention, the solvent of the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution is preferably a polar solvent, and the polar solvent preferably includes one or more of heptanoic acid, octylbenzene, and furan, and is more preferably heptanoic acid. In the present invention, the concentration of the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution is preferably 0.001 to 0.002 mol / mL, specifically preferably 0.001 mol / mL, 0.0015 mol / mL or 0.002 mol / mL. In the present invention, the amount of the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution added is preferably 1 to 2 μL / cm 2 , specifically preferably 1 μL / cm 2 After the dropwise addition of the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution is completed, the 1,2-bis(4-pyridyl)ethane solution is preferably directly added dropwise in the present invention.

[0038] In the present invention, the solvent of the 1,2-bis(4-pyridyl)ethane solution is preferably consistent with the solvent of the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution, which will not be repeated here. In the present invention, the concentration of the 1,2-bis(4-pyridyl)ethane solution is preferably 0.001 to 0.002 mol / mL, specifically preferably 0.001 mol / mL, 0.0015 mol / mL or 0.002 mol / mL. In the present invention, the amount of the 1,2-bis(4-pyridyl)ethane solution added is preferably 1 to 2 μL / cm 2 , specifically preferably 1 μL / cm 2 .

[0039] In the present invention, in the mixed system formed by the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and the 1,2-bis(4-pyridyl)ethane solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane is preferably 1 to 1.5:1, specifically preferably 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1; the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid is preferably 0.0005 to 0.002 mol / mL, specifically preferably 0.0005 mol / mL, 0.00075 mol / mL or 0.001 mol / mL, and the pH value is preferably 6.0 to 7.5.

[0040] In the present invention, the temperature of the first self-assembly is preferably room temperature, and the time is preferably 8 to 15 minutes, more preferably 10 minutes. After the first self-assembly, the present invention preferably further comprises evaporating the solvent, and the temperature of the evaporation is preferably 50 to 70°C, more preferably 60°C. The present invention does not impose a specific limit on the time of the evaporation of the solvent, as long as the solvent can be completely removed.

[0041] In the present invention, the flowchart of the first self-assembly is as follows Figure 1 As shown, specifically: first prepare 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and 1,2-bis(4-pyridyl)ethane solution, and mechanically peel off the substrate 1; then drop 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution on the surface of the substrate 1 to form a disordered two-dimensional supramolecular film 2, and then drop 1,2-bis(4-pyridyl)ethane solution for self-assembly to obtain a nano-periodic structure two-dimensional supramolecular film 3.

[0042] In the present invention, the self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate preferably includes the following steps: sequentially adding 1,2-bis(4-pyridyl)ethane solution and 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution to the substrate for self-assembly (referred to as the second self-assembly).

[0043] In the present invention, the solvent, concentration and dropwise addition amount of the 1,2-bis(4-pyridyl)ethane solution and the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution are preferably consistent with those of the above-mentioned technical solution and are not described in detail herein. In the present invention, in the mixed system formed by the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and the 1,2-bis(4-pyridyl)ethane solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane, the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and the pH value are preferably consistent with those of the above-mentioned technical solution and are not described in detail herein.

[0044] In the present invention, the temperature, time and post-treatment of the second self-assembly are preferably consistent with the above technical solution, and will not be repeated here.

[0045] In the present invention, the self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate preferably includes the following steps: dropwise adding a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid / 1,2-bis(4-pyridyl)ethane mixed solution on the substrate to carry out self-assembly (referred to as the third self-assembly). In the present invention, in the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid / 1,2-bis(4-pyridyl)ethane mixed solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid to 1,2-bis(4-pyridyl)ethane is preferably 1 to 1.5:1, specifically preferably 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1; the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid is preferably 0.0005 to 0.002 mol / mL, specifically preferably 0.0005 mol / mL, 0.00075 mol / mL or 0.001 mol / mL; and the pH value is preferably 6.0 to 7.5.

[0046] In the present invention, the temperature, time and post-treatment of the third self-assembly are preferably consistent with the above technical solution, which will not be described in detail here.

[0047] In the present invention, self-assembly is a bottom-up process for preparing nanoperiodic two-dimensional supramolecular films. This bottom-up process allows for more precise control of the morphology, size, and properties of the nanostructures, resulting in high precision and high performance. By regulating the conditions for self-assembly, the length, linewidth, and duty cycle of the nanostructures can be modulated. Furthermore, the preparation method of the present invention yields cross-scale nanostructures. Furthermore, the preparation method of the present invention is simple to operate, low-cost, and easily scalable, making it suitable for large-scale production applications.

[0048] The present invention also provides the use of the nano-geometric quantity standard sample described in the above technical solution or the nano-geometric quantity standard sample prepared by the preparation method described in the above technical solution in nano-measurement.

[0049] In the present invention, the application devices of the nano-geometric quantity standard sample preferably include a scanning tunneling microscope and an atomic force microscope; the nano-geometric quantity standard sample can be used for calibration and traceability of the scanning tunneling microscope and the atomic force microscope.

[0050] The nano-geometric quantity standard sample provided by the present invention, its preparation method and application are described in detail below in conjunction with the embodiments, but they should not be understood as limiting the scope of protection of the present invention.

[0051] Example 1

[0052] 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid was dissolved in heptanoic acid to obtain a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution with a concentration of 0.001 mol / mL.

[0053] 1,2-bis(4-pyridyl)ethane was dissolved in heptanoic acid to obtain a 1,2-bis(4-pyridyl)ethane solution with a concentration of 0.001 mol / mL.

[0054] The highly oriented cracked graphite substrate is mechanically exfoliated to prepare a clean substrate surface.

[0055] On the clean substrate surface, the 2 A 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution was added dropwise to cover the surface of the substrate, thereby forming a large-scale disordered two-dimensional supramolecular film.

[0056] On the surface of a large-scale disordered two-dimensional supramolecular film, the 2A 1,2-bis(4-pyridyl)ethane solution was added dropwise, and self-assembly was carried out for 10 minutes. After the addition of the 1,2-bis(4-pyridyl)ethane solution, the concentration of 1,2-bis(4-pyridyl)ethane in the resulting mixed system was 0.0005 mol / mL, the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid was 0.0005 mol / mL, the pH value of the mixed system was 6.5, and the ambient temperature was 25°C. The solvent was removed to obtain a nano-geometric standard sample.

[0057] Figure 2 The nano-grid STM image of the nano-periodic structure two-dimensional supramolecular film in the obtained nano-geometric standard sample is as follows: Figure 2 As shown, the line width a in the A direction of the grid structure is 4.55 nanometers, and the line width b in the B direction is 1.90 nanometers. The line width is uniform, the structure is neat, and the periodicity is good.

[0058] The preparation method of the present invention enables the fabrication of high-precision, stable, and cross-scale nanoscale one- or two-dimensional grid standard templates on substrate surfaces. By controlling self-assembly, the periodicity of the geometric structure and the duty cycle can be regulated, enabling precise control of the nanoscale one- or two-dimensional grids. This method complements existing nanoscale one- or two-dimensional grid standard templates and promotes the rapid development of related disciplines and industries. The nanoscale geometric standard templates produced by the present invention are suitable for calibration and traceability in scanning tunneling microscopes, atomic force microscopes, and other applications.

[0059] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A nano-geometric standard sample, characterized in that: The invention comprises a substrate and a nano-periodic structure two-dimensional supramolecular film attached to the substrate. The nano-periodic structure two-dimensional supramolecular film is obtained by self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane.

2. The nano-geometric standard sample according to claim 1, characterized in that: The substrate is made of highly oriented pyrolysis graphite, gold or copper.

3. The method for preparing the nano-geometric standard sample according to claim 1 or 2, characterized in that: The following steps are involved: providing a substrate; 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane are self-assembled on the substrate to obtain the nano-geometric quantity standard sample.

4. The preparation method according to claim 3, characterized in that The self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate comprises the following steps: sequentially dropping a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and a 1,2-bis(4-pyridyl)ethane solution on the substrate for self-assembly.

5. The preparation method according to claim 3, characterized in that The self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate comprises the following steps: sequentially dropping 1,2-bis(4-pyridyl)ethane solution and 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution on the substrate for self-assembly.

6. The preparation method according to claim 3, characterized in that The self-assembly of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid and 1,2-bis(4-pyridyl)ethane on the substrate comprises the following steps: dropwise adding a 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid / 1,2-bis(4-pyridyl)ethane mixed solution on the substrate for self-assembly.

7. The preparation method according to claim 4 or 5, characterized in that In the mixed system formed by the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid solution and the 1,2-bis(4-pyridyl)ethane solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid to 1,2-bis(4-pyridyl)ethane is 1 to 1.5:1, the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid is 0.0005 to 0.002 mol / mL, and the pH value is 6 to 7.

5.

8. The preparation method according to claim 6, characterized in that In the 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid / 1,2-bis(4-pyridyl)ethane mixed solution, the molar ratio of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid to 1,2-bis(4-pyridyl)ethane is 1-1.5:1, the concentration of 5,5'-(9H-fluorene-2,7-diyl)diphthalic acid is 0.0005-0.002 mol / mL, and the pH value is 6-7.

5.

9. The preparation method according to claim 3, characterized in that The substrate was mechanically peeled off before use.

10. Use of the nano-geometric quantity standard sample according to any one of claims 1 to 2 or the nano-geometric quantity standard sample prepared by the preparation method according to any one of claims 3 to 9 in nano-measurement.

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