阅读说明：本技术 半导体超表面电磁波吸收器及其制备方法 (Semiconductor super-surface electromagnetic wave absorber and preparation method thereof ) 是由 刘晓山 钟浩宗 付国兰 刘桂强 刘正奇 于 2019-10-14 设计创作，主要内容包括：本发明提供了一种半导体超表面电磁波吸收器及其制备方法。该半导体超表面电磁波吸收器包括基底层、非金属介质层和超材料结构层,非金属介质层连接于基底层上表面,超材料结构层连接于非金属介质层上表面；其中,超表面结构层由若干单元结构周期性排列组成,每个单元结构包含两个互相平行的长方体。本发明通过合理设计改变超表面的结构参数和入射光的偏振角度,可以定量化的调控其工作频率和工作效率；实现了工作频率与工作效率的双重可定量化调控,拓展了此类吸收器在光电检测、光电转换以及电磁能量吸收等领域的应用前景。(The invention provides a semiconductor super-surface electromagnetic wave absorber and a preparation method thereof. The semiconductor super-surface electromagnetic wave absorber comprises a substrate layer, a non-metal dielectric layer and a metamaterial structure layer, wherein the non-metal dielectric layer is connected to the upper surface of the substrate layer, and the metamaterial structure layer is connected to the upper surface of the non-metal dielectric layer; the super-surface structure layer is formed by periodically arranging a plurality of unit structures, and each unit structure comprises two parallelepipeds. The invention can quantitatively regulate and control the working frequency and the working efficiency of the super-surface by reasonably designing and changing the structural parameters of the super-surface and the polarization angle of incident light; the dual quantitative regulation and control of the working frequency and the working efficiency are realized, and the application prospect of the absorber in the fields of photoelectric detection, photoelectric conversion, electromagnetic energy absorption and the like is expanded.)

1. A semiconductor super-surface electromagnetic wave absorber is characterized in that: the metamaterial-based composite structure comprises a substrate layer, a nonmetal dielectric layer and a metamaterial structure layer, wherein the nonmetal dielectric layer is connected to the upper surface of the substrate layer, and the metamaterial structure layer is connected to the upper surface of the nonmetal dielectric layer; the super-surface structure layer is formed by periodically arranging a plurality of unit structures, and each unit structure comprises two parallelepipeds.

2. The semiconductor super surface electromagnetic wave absorber of claim 1, wherein: the thickness of the substrate layer is 100-300 nanometers, the thickness of the non-metal dielectric layer is 1-50 nanometers, and the thickness of the super-surface structure layer is 200-400 nanometers.

3. The semiconductor super surface electromagnetic wave absorber according to claim 1 or 2, characterized in that: the arrangement period of a plurality of unit structures in the super surface structure layer is 500 nanometers, and the distance between two cuboids in each unit structure is 40 nanometers.

4. The semiconductor super surface electromagnetic wave absorber of claim 3, wherein: the length of the cuboid is 400 nanometers, the width of the cuboid is 60 nanometers, and the height of the cuboid is the same as the thickness of the super-surface structure layer.

5. The semiconductor super surface electromagnetic wave absorber of claim 3, wherein: the substrate layer is made of an opaque refractory metal material, the non-metal dielectric layer is made of aluminum oxide, and the super-surface structure layer is made of silicon.

6. The semiconductor super surface electromagnetic wave absorber of claim 5, wherein: the opaque refractory metal material is gold, silver, copper or aluminum.

7. The method for manufacturing a semiconductor super surface electromagnetic wave absorber as claimed in claim 1, comprising the steps of:

step 1, preparing a clean silicon wafer;

step 2, depositing an opaque refractory metal material on the silicon wafer by using a film coating technology to form a substrate layer;

3, depositing a non-metal medium with a specific thickness on the substrate layer by using a coating technology to form a non-metal medium layer;

step 4, depositing a semiconductor material with a specific thickness on the nonmetal dielectric layer by using a film coating technology to form a semiconductor structure layer;

and 5, etching the semiconductor structure layer by using a mask-free electron beam etching or focused ion beam etching technology to obtain a double-cuboid-shaped periodically-arranged structure, and forming a super-surface structure layer to obtain the semiconductor super-surface electromagnetic wave absorber.

8. The method of claim 7, wherein: the coating technology in the step 2, the step 3 and the step 4 is a magnetron sputtering method, an electron beam evaporation method, a pulse laser deposition method or an atomic layer deposition method.

9. The method according to claim 7 or 8, characterized in that: the non-transparent refractory metal material is gold, silver, copper or aluminum, the non-metal medium is aluminum oxide, and the semiconductor material is silicon.

Technical Field

The invention relates to a semiconductor device, in particular to a semiconductor super-surface electromagnetic wave absorber and a preparation method thereof.

Background

With the rapid development of modern science and technology, electromagnetic wave absorbers have been the hot topic in the scientific and technological field, and the electromagnetic wave absorber capable of quantitatively regulating and controlling the working frequency or working efficiency has wide application prospect in the fields of photoelectric detection, photoelectric conversion, electromagnetic energy absorption and the like.

In recent years, in terms of electromagnetic wave absorbers, various structures have been designed, such as planar metal/dielectric structures, reflective metal grating structures, metamaterial structures, and surface plasmon-based structures. There are many schemes for realizing full absorption based on a plasmon metamaterial system in the aspects of photoelectric detection and selective absorption of electromagnetic wave energy, and a metal substrate-dielectric layer-metamaterial structure layer material system is one of typical structures for realizing perfect absorption. Compared with the traditional method, the system has the characteristic of sub-wavelength, and the overall thickness of the general system is only one hundredth of the working wavelength. However, the working band and the working efficiency of the structure cannot be regulated and controlled quantitatively, so that designing an absorber capable of regulating and controlling the working band and the working efficiency quantitatively is a great challenge in the field.

In practice, the fields of photoelectric detection, photoelectric conversion, electromagnetic energy absorption and the like often need selective absorption of electromagnetic waves in specific wave bands, so that the absorber capable of quantitatively regulating and controlling the working wave bands has wide application prospects. Most of the existing electromagnetic wave metamaterial absorbers can be designed for metamaterial structures so as to regulate and control working bands. Although the working wave band can be changed by changing the parameters of the metamaterial structure, the metamaterial cannot be quantitatively regulated and controlled. Meanwhile, if the working efficiency of the absorber can be quantitatively regulated, the electromagnetic wave absorber has wide application prospect.

Therefore, the design and realization of the quantitative regulation and control of the working frequency and the working efficiency of the electromagnetic wave absorber have very important practical significance and application value.

Disclosure of Invention

The invention aims to provide a semiconductor super-surface electromagnetic wave absorber and a preparation method thereof.

The invention provides a semiconductor super-surface electromagnetic wave absorber which comprises a substrate layer, a non-metal dielectric layer and a metamaterial structure layer, wherein the non-metal dielectric layer is connected to the upper surface of the substrate layer; the super-surface structure layer is formed by periodically arranging a plurality of unit structures, and each unit structure comprises two parallelepipeds.

Further, the thickness of the substrate layer is 100-300 nanometers, the thickness of the non-metal dielectric layer is 1-50 nanometers, and the thickness of the super-surface structure layer is 200-400 nanometers.

Further, the arrangement period of a plurality of unit structures in the super-surface structure layer is 500 nanometers, and the distance between two cuboids in each unit structure is 40 nanometers.

Further, the length of the cuboid is 400 nanometers, the width of the cuboid is 60 nanometers, and the height of the cuboid is the same as the thickness of the super-surface structure layer.

Further, the substrate layer is made of an opaque refractory metal material, and the opaque refractory metal material may be gold, silver, copper or aluminum. The non-metal dielectric layer is made of aluminum oxide. The super-surface structure layer is made of silicon.

The preparation method of the semiconductor super-surface electromagnetic wave absorber comprises the following steps:

step 1, preparing a clean silicon wafer;

step 2, depositing an opaque refractory metal material on the silicon wafer by using a film coating technology to form a substrate layer;

3, depositing a non-metal medium with a specific thickness on the substrate layer by using a coating technology to form a non-metal medium layer;

step 4, depositing a semiconductor material with a specific thickness on the nonmetal dielectric layer by using a film coating technology to form a semiconductor structure layer;

and 5, etching the semiconductor structure layer by using a mask-free electron beam etching or focused ion beam etching technology to obtain a double-cuboid-shaped periodically-arranged structure, and forming a super-surface structure layer to obtain the semiconductor super-surface electromagnetic wave absorber.

Further, the coating technology in the step 2, the step 3 and the step 4 is a magnetron sputtering method, an electron beam evaporation method, a pulse laser deposition method or an atomic layer deposition method.

Further, the opaque refractory metal material is gold, silver, copper or aluminum, the non-metal medium is aluminum oxide, and the semiconductor material is silicon.

The gain effect of the invention is as follows: the invention provides an absorber capable of adjusting and controlling working frequency and working efficiency in a dual-quantification mode, and solves the problem that the working efficiency and the working frequency cannot be adjusted in a quantification mode in the prior art. The semiconductor super-surface electromagnetic wave absorber comprises a substrate layer, a non-metal dielectric layer and a metamaterial structure layer, wherein the super-surface structure is formed by periodically arranging unit structures, each unit structure comprises two paralleled cuboids, and a good coupling environment is provided for an incident light field; by changing the structural parameters of the super surface and the polarization angle of incident light, the working frequency and the working efficiency of the super surface can be regulated and controlled in a double-quantification manner.

Drawings

Fig. 1 is a schematic perspective view of a semiconductor super-surface electromagnetic wave absorber according to the present invention.

FIG. 2 is a schematic cross-sectional view of a semiconductor super-surface electromagnetic wave absorber according to the present invention.

FIG. 3 is an absorption spectrum of the semiconductor super-surface electromagnetic wave absorber of example 1 of the present invention.

FIG. 4 is a graph showing the relationship between the operating frequency of the semiconductor super-surface electromagnetic wave absorber and the thickness of the super-surface structure layer in embodiments 1 to 5 of the present invention.

Fig. 5 and 6 are graphs showing the relationship between the operating efficiency and the polarization angle of incident light for the semiconductor super-surface electromagnetic wave absorber in example 1 of the present invention.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments.

The semiconductor super-surface electromagnetic wave absorber can be prepared according to the following steps:

step 1, preparing a silicon wafer, ultrasonically cleaning the silicon wafer by using absolute ethyl alcohol, acetone and deionized water in sequence, and then drying the silicon wafer to obtain a pure silicon wafer;

step 2, plating a layer of opaque refractory metal material on the surface of the pure silicon wafer by utilizing a magnetron sputtering technology to form a substrate layer;

step 3, depositing a non-metal material with a specific thickness on the substrate layer by utilizing a magnetron sputtering technology to form a non-metal dielectric layer;

step 4, depositing a semiconductor material with a specific thickness on the nonmetal dielectric layer by utilizing a magnetron sputtering technology to form a semiconductor structure layer;

and 5, etching the semiconductor structure layer by using a mask-free electron beam etching to obtain a double-cuboid-shaped periodically arranged structure, and forming a super-surface structure layer to obtain the semiconductor super-surface electromagnetic wave absorber.

As shown in fig. 2, the prepared semiconductor super-surface electromagnetic wave absorber sequentially comprises a substrate layer 1, a non-metal dielectric layer 2 and a super-surface structure layer 3 from bottom to top, wherein the super-surface structure layer 3 is connected to the upper surface of the non-metal dielectric layer 2, and the non-metal dielectric layer 2 is connected to the upper surface of the substrate layer 1. The material of the substrate layer 1 may be an opaque refractory metal material, for example: gold, silver, copper, aluminum. The material of the non-metal dielectric layer 2 may be aluminum oxide. The material of the super surface structure layer 3 can be silicon, the super surface structure layer 3 is formed by periodically arranging unit structures 4, and each unit structure 4 comprises two parallelepipeds 5.

The super-surface structure layer 3 and the nonmetal dielectric layer 2 form an upper layer resonance structure and a lower layer resonance structure, a good coupling environment is provided for an incident light field, and the substrate layer 1 is made of a fireproof metal material and generates plasmon resonance response with electromagnetic waves. The metal base layer 1 has a thickness exceeding 150 nm and suppresses light transmission. By changing the structural parameters of the super-surface structure layer 3 and the polarization angle of incident light, the working frequency and the working efficiency of the super-surface structure layer can be regulated and controlled in a double-quantification manner.

By changing the thickness and the etching condition of each layer, the semiconductor super-surface electromagnetic wave absorber with different structural parameters can be obtained. The following table shows the preparation conditions and the structural parameters of the semiconductor super-surface electromagnetic wave absorbers of examples 1 to 5.

The semiconductor super-surface electromagnetic wave absorbers of examples 1 to 5 were tested. The testing method is to test the reflection (R) and transmission (T) light of the absorber by a grating spectrometer, such as a Lambda 750 spectrum testing system and a reflection light testing module thereof. The commonly used definition of spectral absorptance (a) is used: and A is 1-R-T, namely, an absorption spectrum chart of the absorber can be obtained. By adding the polaroid in the test light path, the polarization angle can be continuously adjusted from 0 degree to 90 degrees, so that the test of measuring the reflection spectrum and the transmission spectrum under different polarization angles is realized, and further, the absorption spectrum under different polarization angles is obtained.

As shown by the curves in fig. 3, the semiconductor super-surface electromagnetic wave absorber of example 1 has four absorption peaks in total. At an operating wavelength of λ₁When 823 nm, the absorption rate reaches 96%. At an operating wavelength of λ₂677 nm and λ₃At 655 nm, the absorbances were 98% and 99%, respectively. The main absorption peak is at the working wavelength of lambda₄The absorption rate reaches 100 percent when the absorption rate is 606 nanometers.

FIG. 4 shows the wavelength at which four absorption peaks are present as a function of the thickness of the super-surface layer. It can be seen that the wavelength at which the absorption peak is located satisfies the formula λ_i＝C₁+C₂X h. Wherein h is the thickness of the super-surface structure layer, namely the height of the cuboid; c₁And C₂Are constants, the value of each of which can be known from fig. 4.

It can be seen that the quantitative regulation and control of the working wavelength can be realized by regulating and controlling the thickness of the super-surface structure layer.

The semiconductor super-surface electromagnetic wave absorber of example 1 was tested with incident light of different polarization angles, and the variation range of the polarization angle of the incident light was 0 to 90 degrees. As shown in fig. 5 and 6, respectivelyThe semiconductor super-surface electromagnetic wave absorber of example 1 has a wavelength of λ₁823 nm, λ₂677 nm, λ₃655 nanometers and λ₄Working efficiency versus incident light polarization angle is plotted at 606 nm.

The absorption efficiency of the absorber can be quantitatively regulated and controlled according to Malus law, and the absorption linear rate of the absorber is A₀X (cos θ) ^ 2. As can be seen from fig. 4 and 5, the absorber efficiency predicted from the malus law is quite consistent with the actual absorber efficiency. Wherein the Malus law is: strength of I₀After passing through the analyzer, the intensity of the transmitted light (without taking absorption into consideration) is I-I₀X (cos θ) ^2(θ is the angle between the light vibration direction of incident linearly polarized light and the polarization direction of the polarizing plate).

In conclusion, the semiconductor super-surface electromagnetic absorber can quantitatively regulate and control the working frequency and the working efficiency, realizes double quantitative regulation and control of the working frequency and the working efficiency, and has wide application prospects in the fields of photoelectric detection, photoelectric conversion, electromagnetic energy absorption and the like.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.