SOI wafer with asymmetric silicon nanoparticle array structure and preparation method

Abstract

The present invention relates to an SOI wafer with an asymmetric silicon nanoparticle array structure and a preparation method. The SOI wafer comprises: a silicon substrate layer, a silicon dioxide buried layer and a silicon nanoparticle array; the nanoparticle array is composed of an even number of primitives arranged periodically; a single primitive comprises two cuboid nanoparticles of different sizes, arranged in parallel or in a straight line; in the parallel or straight line arrangement, the first cuboid nanoparticle is located on one side of the second cuboid nanoparticle; the line connecting the center point of the first cuboid nanoparticle and the center point of the second cuboid nanoparticle is used as the symmetry axis; the first cuboid nanoparticle and the second cuboid nanoparticle are respectively arranged in an axisymmetric manner about the symmetry axis. The asymmetric structure adopted by the silicon nanoparticle array of the present invention enhances the local field strength of the optical signal, further enhances the nonlinear effect of the silicon nanoparticle array in combination with the nonlinearity of the silicon material, and simplifies the processing technology.

Description

Technical Field

[0001] The present invention relates to the technical field of optical devices, and in particular to an SOI wafer with an asymmetric silicon nanoparticle array structure and a preparation method thereof. Background Art

[0002] The nonlinear effect originates from the interaction between light and waveguide, that is, the electric field of the optical signal and the outer electrons of the atoms resonate to produce nonlinear polarization. Nanoparticle arrays made of metals, such as gold (Au), silver (Ag), and copper (Cu), can highly localize the energy of the optical field on the metal surface and exhibit nonlinear effects.

[0003] Compared with the above-mentioned metal materials, the Raman gain coefficient of silicon is 3000 times that of quartz material and depends on polarization characteristics. The wavelength range is less than 2.2μm transparent range, and it itself shows obvious nonlinear optical characteristics. The nonlinear refractive index is 200 times that of commonly used quartz materials. Therefore, silicon material has a strong beam limiting effect, which is very beneficial to the interaction of light and the control of optical waveguide size. It is a very good nonlinear optical carrier. Other advantages of silicon include: low price and allowing transparent transmission of spectral components with wavelengths exceeding 1.1μ. Therefore, the nanoparticle array structure prepared from silicon material can effectively control the transmission of optical signals in nanoscale nonlinear optical elements. At the same time, due to the radiation loss of the silicon nanoparticle array structure (radiation loss refers to the loss caused by the leakage of a part of the optical signal), the array structure reduces its own nonlinear effect, thereby limiting its application in nanoscale nonlinear optical elements.

[0004] At present, asymmetric open resonant rings and L-shaped, triangular and other super-functional primitives are usually used in nanoparticle array structures to tightly confine light on the surface of the structure, which improves the nonlinear effect to a certain extent. However, the processing technology of open resonant rings and L-shaped, triangular and other super-functional primitives is too complicated, and when applied to integrated nanoparticle array structures, the integration efficiency is low and the preparation cost is high. Therefore, it is very important to design an asymmetric silicon nanoparticle array structure with simple preparation technology and high nonlinearity. Summary of the invention

[0005] The purpose of the present invention is to provide a SOI wafer with an asymmetric silicon nanoparticle array structure and a preparation method thereof, so as to enhance the nonlinear effect of the silicon nanoparticle array structure and simplify the processing technology.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A SOI wafer with an asymmetric silicon nanoparticle array structure, comprising: a silicon substrate layer, a silicon dioxide buried layer located on the upper surface of the silicon substrate layer, and a silicon nanoparticle array located on the upper surface of the silicon dioxide buried layer;

[0008] The nanoparticle array is composed of an even number of periodic units; a single unit includes two rectangular nanoparticles of different sizes, namely a first rectangular nanoparticle and a second rectangular nanoparticle; a single unit is located in a unit cell area on the upper surface of the silicon dioxide buried layer; the two rectangular nanoparticles of different sizes in the single unit are arranged in parallel or in a straight line, and the unit cell area is a square area or a rectangular area; in the parallel arrangement or the straight line arrangement, the first rectangular nanoparticle is located on one side of the second rectangular nanoparticle; the line connecting the center point of the first rectangular nanoparticle and the center point of the second rectangular nanoparticle is used as the axis of symmetry; the first rectangular nanoparticle and the second rectangular nanoparticle are respectively arranged in an axisymmetric manner about the axis of symmetry.

[0009] Optionally, in the parallel arrangement, the first rectangular nanoparticle and the second rectangular nanoparticle are parallel in the length direction; the first rectangular nanoparticle and the second rectangular nanoparticle are separated by a preset distance in the width direction; and the unit cell area is a square area.

[0010] Optionally, in the linear arrangement, the first rectangular nanoparticle and the second rectangular nanoparticle are parallel in the width direction; the first rectangular nanoparticle and the second rectangular nanoparticle are separated by a preset distance in the length direction; and the cell area is a rectangular area.

[0011] Optionally, the number of the primitives is between 40 and 300.

[0012] A method for preparing an SOI wafer having an asymmetric silicon nanoparticle array structure, the method comprising:

[0013] preparing a silicon substrate layer;

[0014] Burying a layer of silicon dioxide material on the upper surface of the silicon substrate layer to form a silicon dioxide buried layer;

[0015] Prepare a silicon material core layer on the upper surface of the silicon dioxide buried layer;

[0016] A silicon nanoparticle array is etched on the silicon material core layer to form an SOI wafer with an asymmetric silicon nanoparticle array structure; the nanoparticle array is composed of an even number of periodic units; a single unit includes two rectangular nanoparticles of different sizes, namely a first rectangular nanoparticle and a second rectangular nanoparticle; a single unit is located in a unit cell area on the upper surface of the silicon dioxide buried layer; the two rectangular nanoparticles of different sizes in the single unit are arranged in parallel or in a straight line, and the unit cell area is a square area or a rectangular area; in the parallel arrangement or the straight arrangement, the first rectangular nanoparticle is located on one side of the second rectangular nanoparticle; the line connecting the center point of the first rectangular nanoparticle and the center point of the second rectangular nanoparticle is used as the symmetry axis; the first rectangular nanoparticle and the second rectangular nanoparticle are respectively arranged in an axisymmetric manner about the symmetry axis.

[0017] Optionally, the preparation method further comprises: mechanically polishing, removing impurities, cleaning and drying the SOI wafer to form a finished SOI wafer.

[0018] Optionally, in the parallel arrangement, the first rectangular nanoparticle and the second rectangular nanoparticle are parallel in the length direction; the first rectangular nanoparticle and the second rectangular nanoparticle are separated by a preset distance in the width direction; and the unit cell area is a square area.

[0019] Optionally, in the linear arrangement, the first rectangular nanoparticle and the second rectangular nanoparticle are parallel in the width direction; the first rectangular nanoparticle and the second rectangular nanoparticle are separated by a preset distance in the length direction; and the cell area is a rectangular area.

[0020] Optionally, the number of the primitives is between 40 and 300.

[0021] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0022] The present invention provides an SOI wafer with an asymmetric silicon nanoparticle array structure and a preparation method thereof. The SOI wafer with an asymmetric silicon nanoparticle array structure comprises: a silicon substrate layer, a silicon dioxide buried layer and a silicon nanoparticle array; the nanoparticle array is composed of an even number of primitives arranged periodically; a single primitive comprises two cuboid nanoparticles of different sizes, namely a first cuboid nanoparticle and a second cuboid nanoparticle; the single primitive is located in a unit cell area on the upper surface of the silicon dioxide buried layer; the two cuboid nanoparticles of different sizes in the single primitive are arranged in parallel or in a straight line, and the unit cell area is a square area or a rectangular area; in the parallel arrangement or the straight line arrangement, the first cuboid nanoparticle is located on one side of the second cuboid nanoparticle; a line connecting the center point of the first cuboid nanoparticle and the center point of the second cuboid nanoparticle is used as a symmetry axis; the first cuboid nanoparticle and the second cuboid nanoparticle are respectively arranged in an axisymmetric manner about the symmetry axis. The asymmetric structure adopted by the silicon nanoparticle array of the present invention enhances the local field strength of the optical signal, and the nonlinear combination with the silicon material further enhances the nonlinear effect of the silicon nanoparticle array; compared with open resonant rings and L-shaped, triangular and other super-functional primitives, the rectangular nanoparticles adopted by the primitives of the present invention are easier to process and simplify the processing technology. Therefore, the primitive structure composed of rectangular nanoparticles of the present invention has higher processing efficiency and lower preparation cost when applied to an integrated nanoparticle array structure, and provides a practical solution for nonlinear optical elements to efficiently realize beam control, holographic imaging, optical image encryption and other functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 A schematic structural diagram of an SOI wafer having an asymmetric silicon nanoparticle array structure provided by an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of the structure of a single unit in a silicon nanoparticle array provided by an embodiment of the present invention;

[0026] Figure 3 A top view of a layout of a first cuboid nanoparticle and a second cuboid nanoparticle arranged in parallel in a single primitive provided by an embodiment of the present invention;

[0027] Figure 4 A top view of another layout of a parallel arrangement of a first cuboid nanoparticle and a second cuboid nanoparticle in a single unit provided by an embodiment of the present invention;

[0028] Figure 5 A top view of a layout of a linear arrangement of first cuboid nanoparticles and second cuboid nanoparticles in a single primitive provided by an embodiment of the present invention;

[0029] Figure 6 A top view of another layout of a linear arrangement of first cuboid nanoparticles and second cuboid nanoparticles in a single primitive provided by an embodiment of the present invention;

[0030] Explanation of symbols:

[0031] Silicon substrate layer 1, silicon dioxide buried layer 2, silicon nanoparticle array 3, primitive 4, first cuboid nanoparticle 401, second cuboid nanoparticle 402, unit cell region 5. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The purpose of the present invention is to provide a SOI wafer with an asymmetric silicon nanoparticle array structure and a preparation method thereof, so as to enhance the nonlinear effect of the silicon nanoparticle array structure and simplify the processing technology.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Figure 1 A schematic diagram of the structure of an SOI wafer with an asymmetric silicon nanoparticle array structure provided by an embodiment of the present invention. Figure 1, the SOI wafer with an asymmetric silicon nanoparticle array structure includes: a silicon substrate layer 1, a silicon dioxide buried layer 2 located on the upper surface of the silicon substrate layer 1, and a silicon nanoparticle array 3 located on the upper surface of the silicon dioxide buried layer 2. The nanoparticle array 3 is composed of an even number of primitives 4 arranged periodically. In practical applications, the nanoparticle array 3 can be arranged in a periodic manner of m rows and n columns. In this periodic arrangement, the number of primitives 4 p=m×n, where m represents the number of rows of the asymmetric nanoparticle array structure, n represents the number of columns of the asymmetric nanoparticle array structure, and n is an even number. Preferably, the number p of the primitives 4 is between 40 and 300.

[0036] Figure 2 A schematic diagram of the structure of a single unit in a silicon nanoparticle array provided by an embodiment of the present invention. Figure 2 , a single unit cell 4 includes two cuboid nanoparticles of different sizes, namely a first cuboid nanoparticle 401 and a second cuboid nanoparticle 402. p units 4 are periodically arranged on the upper surface of the silicon dioxide buried layer 2, and the bottom surfaces of the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 included in a single unit cell 4 are both in contact with the upper surface of the silicon dioxide buried layer 2, and the single unit cell 4 is located in a unit cell area 5 on the upper surface of the silicon dioxide buried layer 2, as shown in FIG. Figures 3 to 6 The two sides of the bottom surface of the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 are respectively called the length L and width W of the cuboid nanoparticle, and the side perpendicular to the bottom surface is called the height H of the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402.

[0037] See also Figures 3 to 6 , from a top view, the two cuboid nanoparticles of different sizes in a single unit 4 can be arranged in two ways: parallel arrangement and linear arrangement. The parallel arrangement means that the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 are parallel in the length direction, and the center points of the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 are at a distance D in the width direction, see Figure 3 and Figure 4 The linear arrangement means that the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 are parallel in the width direction, and the center points of the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 are at a distance D in the length direction, see Figure 5 and Figure 6 The length direction refers to the direction parallel to the length L of the cuboid nanoparticle, and the width direction refers to the direction parallel to the width W of the cuboid nanoparticle.

[0038] like Figure 3 and Figure 4 As shown, when the parallel arrangement is adopted, the cell area 5 (the area shown by the dotted box in the figure) is a square area; Figure 5 and Figure 6 As shown, when a straight line arrangement is adopted, the cell area 5 is a rectangular area.

[0039] See also Figures 3 to 6 In the parallel arrangement or the linear arrangement, the first cuboid nanoparticles 401 are all located on one side of the second cuboid nanoparticles 402. The line connecting the center point of the first cuboid nanoparticle 401 and the center point of the second cuboid nanoparticle 402 is used as the symmetry axis; the first cuboid nanoparticles 401 and the second cuboid nanoparticles 402 are respectively arranged in an axisymmetric manner about the symmetry axis.

[0040] like Figure 3 and Figure 4 As shown, in the parallel arrangement, the first rectangular nanoparticle 401 and the second rectangular nanoparticle 402 are parallel in the length direction; the first rectangular nanoparticle 401 and the second rectangular nanoparticle 402 are separated by a preset distance in the width direction; and the cell area 5 is a square area.

[0041] Specifically, when the parallel arrangement is adopted, from a top view, the rectangular nanoparticles 401 and 402 in a primitive 4 have two layouts: the first rectangular nanoparticle 401 is located below the second rectangular nanoparticle 402, such as Figure 3 As shown; or the first cuboid nanoparticle 401 is located above the second cuboid nanoparticle 402, as shown Figure 4 shown.

[0042] like Figure 5 and Figure 6 As shown, in the linear arrangement, the first rectangular nanoparticle 401 and the second rectangular nanoparticle 402 are parallel in the width direction; the first rectangular nanoparticle 401 and the second rectangular nanoparticle 402 are separated by a preset distance in the length direction; and the cell area 5 is a rectangular area.

[0043] Specifically, when the linear arrangement is adopted, from a top view, the rectangular nanoparticles 401 and 402 in a primitive 4 have two layouts: the first rectangular nanoparticle 401 is located on the left side of the second rectangular nanoparticle 402, such as Figure 5 or the first cuboid nanoparticle 401 is located on the right side of the second cuboid nanoparticle 402, as shown in Figure 6 shown.

[0044] like Figures 3 to 6 As shown, the center distance between the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 of the primitive 4 is D, and the value range is 220nm~400nm.

[0045] The first cuboid nanoparticle 401 has three parameters: length L1, width W1, and height H1. The second cuboid nanoparticle 402 has three parameters: length L2, width W2, and height H2.

[0046] As a specific embodiment, the length L1 of the first rectangular nanoparticle 401 is 500nm. The length L2 of the second rectangular nanoparticle 402 is L1-2ΔL. The value range of ΔL is 25nm to 100nm. The width W1 of the first rectangular nanoparticle 401 is 150nm. The width W2 of the second rectangular nanoparticle 402 is consistent with the width W1 of the first rectangular nanoparticle 401, and is also 150nm. The height H1 of the first rectangular nanoparticle 401 is determined by the silicon thickness of the core layer of the SOI wafer (that is, the etching depth of a single element 4) used in actual applications. The height H2 of the second rectangular nanoparticle 402 is also determined by the silicon thickness of the core layer of the SOI wafer used in actual applications, H1=H2.

[0047] In a single unit cell 4 of the silicon nanoparticle array 3 of the present invention, since the first rectangular nanoparticle 401 and the second rectangular nanoparticle 402 have different sizes, the silicon nanoparticle array 3 formed by the periodic arrangement of p units 4 is an asymmetric structure. This asymmetric structure significantly enhances the nonlinear effect of the silicon nanoparticle array 3 while simplifying the processing technology, thereby realizing an asymmetric silicon nanoparticle array structure with high nonlinear effect.

[0048] The present invention also provides a method for preparing the SOI wafer having an asymmetric silicon nanoparticle array structure, the method comprising:

[0049] Step (1): Prepare a silicon substrate layer 1.

[0050] The silicon substrate layer 1 is a silicon material substrate, and the refractive index of the silicon material is about 3.42.

[0051] Step (2): burying a layer of silicon dioxide material on the upper surface of the silicon substrate layer 1 to form a silicon dioxide buried layer 2.

[0052] SOI stands for Silicon-On-Insulator, which means silicon on an insulating substrate. This technology introduces a buried oxide layer between the top silicon and the back substrate. The silicon dioxide buried layer 2 of the present invention uses a silicon dioxide material with a refractive index of about 1.45. The function of the silicon dioxide buried layer 2 is to protect the asymmetric silicon nanoparticle array structure of the core layer.

[0053] Step (3): preparing a core layer of silicon material on the upper surface of the silicon dioxide buried layer 2.

[0054] The core layer structure is made of silicon material, which is used to construct a highly nonlinear asymmetric nanoparticle array structure.

[0055] Step (4): etching a silicon nanoparticle array 3 on the silicon material core layer to form an SOI wafer with an asymmetric silicon nanoparticle array structure.

[0056] The nanoparticle array 3 is composed of an even number of primitives 4 arranged periodically; a single primitive 4 includes two cuboid nanoparticles of different sizes, namely a first cuboid nanoparticle 401 and a second cuboid nanoparticle 402; a single primitive 4 is located in a unit cell area 5 on the upper surface of the silicon dioxide buried layer 2. The two cuboid nanoparticles of different sizes in a single primitive 4 are arranged in parallel or in a straight line, and correspondingly, the unit cell area 5 is a square area or a rectangular area. In the parallel arrangement or the straight line arrangement, the first cuboid nanoparticle 401 is located on one side of the second cuboid nanoparticle 402; the line connecting the center point of the first cuboid nanoparticle 401 and the center point of the second cuboid nanoparticle 402 is used as the symmetry axis; the first cuboid nanoparticle 401 and the second cuboid nanoparticle 402 are respectively arranged in an axisymmetric manner about the symmetry axis.

[0057] Furthermore, the SOI wafer is subjected to mechanical polishing, impurity removal, cleaning and drying processes to form a finished SOI wafer.

[0058] Furthermore, in the parallel arrangement, the first rectangular nanoparticle and the second rectangular nanoparticle are parallel in the length direction; the first rectangular nanoparticle and the second rectangular nanoparticle are separated by a preset distance in the width direction; and the unit cell area is a square area.

[0059] In the linear arrangement, the first rectangular nanoparticle and the second rectangular nanoparticle are parallel in the width direction; the first rectangular nanoparticle and the second rectangular nanoparticle are separated by a preset distance in the length direction; and the unit cell area is a rectangular area.

[0060] The number of the primitives is between 40 and 300.

[0061] The SOI wafer prepared by the method of the present invention adopts a highly nonlinear and asymmetric nanoparticle array structure to enhance the local field strength of the optical signal, and the nonlinear combination with the silicon material further enhances the nonlinear effect of the silicon nanoparticle array. Compared with the open resonant ring and L-shaped, triangular and other super-functional primitives, cuboid nanoparticles are easier to process. Therefore, the primitive structure composed of cuboid nanoparticles in the present invention has higher processing efficiency and lower preparation cost when applied to the integrated nanoparticle array structure, and provides a practical solution for nonlinear optical elements to efficiently realize beam control, holographic imaging, optical image encryption and other functions.

[0062] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0063] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A SOI wafer having an asymmetric silicon nanoparticle array structure, characterized in that: include: A silicon substrate layer, a silicon dioxide buried layer located on an upper surface of the silicon substrate layer, and a silicon nanoparticle array located on an upper surface of the silicon dioxide buried layer; The nanoparticle array is composed of an even number of primitives arranged periodically; the nanoparticle array adopts a periodic arrangement of m rows and n columns, in which the number of primitives p=m×n, where m represents the number of rows of the asymmetric nanoparticle array structure, n represents the number of columns of the asymmetric nanoparticle array structure, and n is an even number; A single primitive includes two cuboid nanoparticles of different sizes, namely a first cuboid nanoparticle and a second cuboid nanoparticle; the single primitive is located in a unit cell area on the upper surface of the silicon dioxide buried layer; the two cuboid nanoparticles of different sizes in the single primitive are arranged in a straight line, and the unit cell area is a rectangular area; the first cuboid nanoparticle is located on one side of the second cuboid nanoparticle; a line connecting the center point of the first cuboid nanoparticle and the center point of the second cuboid nanoparticle is used as a symmetry axis; the first cuboid nanoparticle and the second cuboid nanoparticle are respectively arranged in an axisymmetric manner about the symmetry axis; The first cuboid nanoparticle and the second cuboid nanoparticle are parallel in the width direction; the first cuboid nanoparticle and the second cuboid nanoparticle are separated by a preset distance in the length direction; The center distance between the first cuboid nanoparticle and the second cuboid nanoparticle of the primitive is D, and the value range is 220nm~400nm; The first rectangular nanoparticle has three parameters: length L1, width W1, and height H1; the second rectangular nanoparticle has three parameters: length L2, width W2, and height H2; the length L1 of the first rectangular nanoparticle is 500nm; the length L2 of the second rectangular nanoparticle is L1-2ΔL; the value range of ΔL is 25nm to 100nm.

2. The SOI wafer according to claim 1, characterized in that: The number of the primitives is between 40 and 300.

3. A method for preparing a SOI wafer having an asymmetric silicon nanoparticle array structure, characterized in that: The preparation method comprises: preparing a silicon substrate layer; Burying a layer of silicon dioxide material on the upper surface of the silicon substrate layer to form a silicon dioxide buried layer; Prepare a silicon material core layer on the upper surface of the silicon dioxide buried layer; A silicon nanoparticle array is etched on the silicon material core layer to form an SOI wafer with an asymmetric silicon nanoparticle array structure; the nanoparticle array is composed of an even number of primitives arranged periodically; the nanoparticle array adopts a periodic arrangement of m rows and n columns, in which the number of primitives p=m×n, wherein m represents the number of rows of the asymmetric nanoparticle array structure, n represents the number of columns of the asymmetric nanoparticle array structure, and n is an even number; A single primitive includes two cuboid nanoparticles of different sizes, namely a first cuboid nanoparticle and a second cuboid nanoparticle; the single primitive is located in a unit cell area on the upper surface of the silicon dioxide buried layer; the two cuboid nanoparticles of different sizes in the single primitive are arranged in a straight line, and the unit cell area is a rectangular area; the first cuboid nanoparticle is located on one side of the second cuboid nanoparticle; a line connecting the center point of the first cuboid nanoparticle and the center point of the second cuboid nanoparticle is used as a symmetry axis; the first cuboid nanoparticle and the second cuboid nanoparticle are respectively arranged in an axisymmetric manner about the symmetry axis; The first cuboid nanoparticle and the second cuboid nanoparticle are parallel in the width direction; the first cuboid nanoparticle and the second cuboid nanoparticle are separated by a preset distance in the length direction; the center distance between the first cuboid nanoparticle and the second cuboid nanoparticle of the primitive is D, and the value range is 220nm to 400nm; The first rectangular nanoparticle has three parameters: length L1, width W1, and height H1; the second rectangular nanoparticle has three parameters: length L2, width W2, and height H2; the length L1 of the first rectangular nanoparticle is 500nm; the length L2 of the second rectangular nanoparticle is L1-2ΔL; the value range of ΔL is 25nm to 100nm.

4. The preparation method according to claim 3, characterized in that: The preparation method further comprises: mechanically polishing, removing impurities, cleaning and drying the SOI wafer to form a finished SOI wafer.

5. The preparation method according to claim 3, characterized in that: The number of the primitives is between 40 and 300.

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