阅读说明：本技术 一种带光学微腔结构的石墨烯近红外探测器及其制造方法 (Graphene near-infrared detector with optical microcavity structure and manufacturing method thereof ) 是由 蓝镇立 何峰 丁玎 张�浩 于 2020-12-08 设计创作，主要内容包括：本发明公开了一种带光学微腔结构的石墨烯近红外探测器及其制备方法,本探测器包括衬底、石墨烯层和电极层；所述石墨烯层的两侧分别设置有第一透光层和第二透光层,所述衬底与所述第一透光层之间设置有第一反射层,所述电极层与所述第二透光层之间设置有间隔分布的第二反射层,所述第一反射层、第一透光层、第二透光和第二反射层共同形成光学微腔结构。本发明具有结构简单、红外吸收率高、工作稳定可靠等优点。(The invention discloses a graphene near-infrared detector with an optical microcavity structure and a preparation method thereof, wherein the detector comprises a substrate, a graphene layer and an electrode layer; the optical microcavity structure comprises a substrate, an electrode layer, a first euphotic layer, a second euphotic layer, a substrate, a first reflective layer, a second reflective layer and a second reflective layer, wherein the first euphotic layer and the second euphotic layer are arranged on two sides of the graphene layer respectively, the first reflective layer is arranged between the substrate and the first euphotic layer, the second reflective layer is arranged between the electrode layer and the second euphotic layer at intervals, and the first reflective layer, the first euphotic layer, the second light and the second. The invention has the advantages of simple structure, high infrared absorption rate, stable and reliable work and the like.)

1. A graphene near-infrared detector with an optical microcavity structure is characterized by comprising a substrate (1), a graphene layer (4) and an electrode layer (7); the optical micro-cavity structure is characterized in that a first euphotic layer (3) and a second euphotic layer (5) are respectively arranged on two sides of the graphene layer (4), a first reflecting layer (2) is arranged between the substrate (1) and the first euphotic layer (3), second reflecting layers (6) distributed at intervals are arranged between the electrode layer (7) and the second euphotic layer (5), and the first reflecting layer (2), the first euphotic layer (3), the second euphotic layer (5) and the second reflecting layer (6) jointly form an optical micro-cavity structure.

2. The graphene near-infrared detector with the optical microcavity structure according to claim 1, wherein the second reflective layer (6) is strip-shaped and is uniformly distributed on the second transparent layer (5).

3. The graphene near-infrared detector with the optical microcavity structure according to claim 1, wherein a protective layer (8) is further disposed on the electrode layer (7).

4. The graphene near-infrared detector with the optical microcavity structure according to claim 1, 2 or 3, wherein the first reflective layer (2) and the second reflective layer (6) are both thin-film mirror reflective layers.

5. The graphene near-infrared detector with the optical microcavity structure according to claim 1, 2 or 3, wherein the first light-transmitting layer (3) and the second light-transmitting layer (5) are both thin-film light-transmitting layers.

6. A preparation method of the graphene near-infrared detector with the optical microcavity structure as claimed in any one of claims 1 to 5, comprising the steps of:

1) depositing a first reflecting layer (2) and a first light-transmitting layer (3) on the substrate (1) in sequence;

2) preparing a graphene layer (4) on the first light transmitting layer (3);

3) sequentially preparing a second light-transmitting layer (5) and a second reflecting layer (6) on the graphene layer (4);

4) preparing an electrode layer (7) on the second reflective layer (6).

7. The method according to claim 6, wherein in step 3), the specific process of preparing the second reflective layer (6) is as follows:

3.1) manufacturing a glue layer array pattern (9) on the surface of the second light-transmitting layer (5);

3.2) depositing a second reflecting layer (6) on the adhesive layer array pattern (9);

3.3) removing the glue layer array pattern (9) to form second reflecting layers (6) distributed at intervals.

8. The production method according to claim 6, characterized in that after step 4), a protective layer (8) is produced on the electrode layer (7).

9. A method according to any one of claims 6 to 8, wherein the first and second light transmitting layers (3, 5) are made of silicon oxide, silicon nitride or tantalum pentoxide material.

10. The method according to any one of claims 6 to 8, wherein the first reflective layer (2) and the second reflective layer (6) are made of a nickel or aluminum material.

Technical Field

The invention mainly relates to the technical field of infrared detection, in particular to a graphene near-infrared detector with an optical microcavity structure and a manufacturing method thereof.

Background

Graphene is a two-dimensional material composed of a single layer of carbon atoms, and has many excellent physical properties, such as high strength, good ductility, good thermal conductivity, and the like. However, graphene is a hot research point in the field of photoelectric detection mainly because it has unique optical and electrical properties different from those of conventional semiconductor materials, and can be applied to the fields of industrial automatic control, remote sensing imaging, guidance, medical diagnosis, environmental monitoring, optical communication, and the like.

At present, infrared detection materials with high response rate and high detectivity, such as HgCdTe, I nGaAs, quantum well, I I type superlattice and the like, have the disadvantages of harsh preparation conditions, complex process, high cost and low working temperature. Compared with HgCdTe, I nGaAs and other types of red light detectors, the graphene has unique optical and electrical properties different from those of the traditional semiconductor material, and can make up the defects to a certain extent. Due to extremely high electron and hole mobility at room temperature and ultra-wide spectrum light absorption from visible to far infrared, the graphene has great potential in the aspect of realizing uncooled infrared detection with high response speed, wide spectrum, low cost and large area array, and is also the main direction of future development of the graphene infrared detector. In addition, different from a traditional bulk material semiconductor, the electron concentration in the graphene can be controlled in a mode of applying bias voltage, so that the electronic control tuning of a detection waveband is realized. And the preparation of the graphene flexible infrared detector is a new direction for future development by combining the flexibility advantage of the graphene.

Although the graphene has outstanding advantages when used for optical detection, the graphene also has obvious defects: due to low light absorption rate and lack of a light gain mechanism, the graphene has low light response rate of the graphene detector, and cannot meet the requirements of practical application. At present, the photoresponse rate of a graphene detector can be improved to different degrees by various methods such as opening a graphene band gap by means of quantum dot modification, PN junction construction, molecular or metal doping, size quantization and the like of graphene, combining intrinsic graphene and a plasma nanostructure and the like, so as to meet or approach the requirements of practical application.

At present, the method for improving the infrared absorption of graphene mainly realizes the improvement of light absorption and absorption rate of different wave bands by surface adsorption or doping of other elements. Due to the chemical inertness of carbon atoms, intrinsic graphene has limited adsorption capacity to molecules or atoms, basically belongs to the physical adsorption category, and is easily desorbed under the influence of temperature to reduce the performance of a device. Doping tends to affect the intrinsic properties of graphene, resulting in additional signal interference and performance loss.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the problems in the prior art, the invention provides the graphene near-infrared detector with the optical microcavity structure, which has the advantages of simple structure, high infrared absorption rate and stable and reliable work, and correspondingly provides a preparation method with simple preparation.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

a graphene near-infrared detector with an optical microcavity structure comprises a substrate, a graphene layer and an electrode layer; the optical microcavity structure comprises a substrate, a first euphotic layer, a second euphotic layer, a substrate, a first reflecting layer, a second reflecting layer and a second euphotic layer, wherein the first euphotic layer and the second euphotic layer are arranged on two sides of the graphene layer respectively, the first reflecting layer is arranged between the substrate and the first euphotic layer, the second reflecting layer is arranged between the electrode layer and the second euphotic layer at intervals, and the first reflecting layer, the first euphotic layer, the second euphotic layer and the second reflecting.

As a further improvement of the above technical solution:

the second reflecting layer is strip-shaped and is uniformly distributed on the second light-transmitting layer.

And a protective layer is also arranged on the electrode layer.

The first reflecting layer and the second reflecting layer are both thin film mirror surface reflecting layers.

The first euphotic layer and the second euphotic layer are thin film euphotic layers.

The invention also discloses a preparation method of the graphene near-infrared detector with the optical microcavity structure, which comprises the following steps:

1) depositing a first reflecting layer and a first light-transmitting layer on the substrate in sequence;

2) preparing a graphene layer on the first light transmitting layer;

3) sequentially preparing a second light-transmitting layer and a second reflecting layer on the graphene layer;

4) and preparing an electrode layer on the second reflecting layer.

As a further improvement of the above technical solution:

in step 3), the specific process for preparing the second reflective layer is as follows:

3.1) manufacturing a glue layer array pattern on the surface of the second light-transmitting layer;

3.2) depositing on the adhesive layer array pattern to prepare a second reflecting layer;

3.3) removing the glue layer array pattern to form second reflecting layers distributed at intervals.

After step 4), a protective layer is prepared on the electrode layer.

The first light-transmitting layer and the second light-transmitting layer are made of silicon oxide, silicon nitride or tantalum pentoxide materials.

The first reflecting layer and the second reflecting layer are made of nickel or aluminum materials.

Compared with the prior art, the invention has the advantages that:

according to the graphene near-infrared detector with the optical microcavity structure, the optical microcavity structure is formed by the first reflecting layer, the first light-transmitting layer, the second light-transmitting layer and the second reflecting layer; when infrared light enters the detector, the light is reflected for multiple times in the optical microcavity structure, so that the light penetrates through the graphene layer for multiple times, and the infrared absorption rate of the detector is improved; different from adsorption and doping methods, the structural state of the graphene layer is not changed by the optical microcavity structure design, so that the working stability and reliability of the detector can be improved; in addition, the structure is simple and easy to realize.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention.

FIG. 2 is a diagram of a glue line array according to the present invention.

Fig. 3 is a schematic structural diagram of a second reflective layer according to an embodiment of the invention.

FIG. 4 is a schematic structural diagram of an optical microcavity structure according to an embodiment of the present invention.

The reference numbers in the figures denote: 1. a substrate; 2. a first reflective layer; 3. a first light-transmitting layer; 4. a graphene layer; 5. a second light-transmitting layer; 6. a second reflective layer; 7. an electrode layer; 8. a protective layer; 9. and (5) forming a glue layer array pattern.

Detailed Description

The invention is further described below with reference to the figures and the specific embodiments of the description.

As shown in fig. 1, the graphene near-infrared detector with an optical microcavity structure of the present embodiment includes a substrate 1, a graphene layer 4, and an electrode layer 7; the two sides of the graphene layer 4 are respectively provided with a first euphotic layer 3 and a second euphotic layer 5, a first reflecting layer 2 is arranged between the substrate 1 and the first euphotic layer 3, second reflecting layers 6 which are distributed at intervals are arranged between the electrode layer 7 and the second euphotic layer 5, and the first reflecting layer 2, the first euphotic layer 3, the second euphotic layer 5 and the second reflecting layer 6 form an optical microcavity structure together. When infrared light enters the detector, the light is reflected for multiple times in the optical microcavity structure, as shown in fig. 4, so that the light penetrates through the graphene layer 4 for multiple times, and the infrared absorption rate of the detector is improved; different from adsorption and doping methods, the structural state of the graphene layer 4 is not changed by the optical microcavity structure design, so that the working stability and reliability of the detector can be improved; and simple structure and easy realization.

In this embodiment, the second reflective layer 6 is in the shape of a stripe and is uniformly distributed on the second transparent layer 5. The adjacent second reflecting layers 6 facilitate the light to enter. In addition, a protective layer 8 is provided on the electrode layer 7.

In this embodiment, the first reflective layer 2 and the second reflective layer 6 are both thin film mirror reflective layers, and are made of nickel or aluminum materials. The first light-transmitting layer 3 and the second light-transmitting layer 5 are thin film light-transmitting layers and are made of silicon oxide, silicon nitride or tantalum pentoxide materials.

The invention also discloses a preparation method of the graphene near-infrared detector with the optical microcavity structure, which comprises the following steps:

1) depositing a first reflecting layer 2 and a first light-transmitting layer 3 on a substrate 1 in sequence;

2) preparing a graphene layer 4 on the first light transmitting layer 3;

3) a second light-transmitting layer 5 and a second reflecting layer 6 are sequentially prepared on the graphene layer 4;

4) an electrode layer 7 is prepared on the second reflective layer 6.

The preparation method is simple to operate, and the graphene near-infrared detector directly obtained has the advantages of the detector.

In this embodiment, in step 3), the specific process of preparing the second reflective layer 6 is as follows:

3.1) manufacturing a glue layer array pattern 9 on the surface of the second light-transmitting layer 5;

3.2) depositing a second reflecting layer 6 on the adhesive layer array pattern 9;

3.3) removing the glue layer array pattern 9 to form the second reflecting layers 6 distributed at intervals.

In this embodiment, after step 4), a protective layer 8 is prepared on the electrode layer 7.

The above-described overall invention is further illustrated below with reference to a complete embodiment:

1. depositing a low-absorption high-reflection thin film mirror surface first reflection layer 2 on a substrate 1, and then depositing a low-absorption high-transmittance thin film first light transmission layer 3;

2. then transferring the graphene layer 4 to the surface of the first euphotic layer 3 by adopting a wet method to prepare a near-infrared absorption graphene sensitive layer;

3. then, continuously depositing on the surface of the graphene layer 4 to prepare a second light-transmitting thin film layer 5 with low absorption and high transmittance;

4. by utilizing the photoetching technology, a glue layer array pattern 9 is manufactured on the surface of the thin film second euphotic layer 5, as shown in fig. 2; then depositing and preparing a low-absorption high-reflection film mirror surface second reflection layer 6 on the glue layer array pattern 9; removing the glue layer array pattern 9 by a stripping method to form a low-absorption high-reflection film mirror surface second reflection layer 6 shown in figure 3; of course, in other embodiments, other shapes such as circular rings may be used; although the second reflective layer 6 can shield the incident light to some extent, the effect of absorbing light by the optical microcavity structure can greatly offset the adverse effect of the shielding (for example, the second reflective layer 6 can shield 20-50% of the light from entering, and the optical microcavity structure can raise the light absorption from 20% to over 90%);

5. and finally, sequentially depositing and preparing an electrode layer 7 and a protective layer 8 on the thin film mirror surface second reflecting layer 6.

The deposition method of each thin film is a physical or chemical method such as sputtering, electron beam, molecular beam, MOCVD, PCVD, or the like.

The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.