CN111916511B - Superlattice material embedded with quantum wires, preparation method thereof, infrared band luminescent material and detector - Google Patents

Abstract

The invention provides a superlattice material embedded with quantum wires, a preparation method thereof, an infrared band luminescent material and a detector. The superlattice material embedded with the quantum wires comprises at least one InAs/GaSb layer and at least one single material layer which are arranged in a stacked mode; the InAs/GaSb layer comprises an InAs part and a GaSb part, and the single material layer comprises InAs or GaSb; InAs portions and GaSb portions are alternately arranged and have different widths in the arrangement direction. The preparation method of the superlattice material embedded with the quantum wires comprises the following steps: and sequentially growing an InAs/GaSb layer and a single substance layer on the substrate according to the structure. An infrared band light emitting material includes a superlattice material with embedded quantum wires. And the detector comprises an infrared band luminescent material. According to the quantum wire embedded superlattice material, the quantum wires are introduced into the II type superlattice to form a wire-superlattice composite structure, so that the working temperature of a device can be increased, and the photoelectric performance of the material can be improved.

Description

Quantum wire-embedded superlattice material and preparation method thereof, infrared light-emitting material and detector

technical field

The invention relates to the field of semiconductors, in particular to a quantum wire-embedded superlattice material and a preparation method thereof, an infrared band luminescent material and a detector.

Background technique

As important semiconductor optoelectronic materials, III-V semiconductors have attracted much attention in recent years. Based on their lasers with different energy band structures, detectors have shown great application prospects in the fields of national defense and civilian use, and have achieved relatively good results in recent researches. great research progress. Further optimizing the quantum structure of III-V semiconductors and improving the optoelectronic properties of materials will play an important role in promoting the performance of optoelectronic devices.

However, it is not difficult to find that quantum dot structures can only be introduced into quantum well structures based on the I-type band structure at present. In the type II band structure, such as the InAs/GaSb system, there is no relevant report.

In view of this, this application is hereby made.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a quantum wire-embedded superlattice material and a preparation method thereof, an infrared band luminescent material and a detector, so as to solve the above problems.

To achieve the above purpose, the present invention adopts the following technical solutions:

A quantum wire-embedded superlattice material, comprising at least one InAs/GaSb layer and at least one single material layer arranged in layers; the InAs/GaSb layer includes an InAs part and a GaSb part, and the single material layer includes InAs or GaSb ;

The InAs portion and the GaSb portion are alternately arranged in the InAs/GaSb layer and have different widths along the direction of the arrangement;

In the quantum wire-embedded superlattice structure, the composition of at least one of the single material layers is the same as the composition of a large portion of the adjacent InAs/GaSb layer.

Preferably, each of the InAs portion and the GaSb portion has a rectangular parallelepiped shape.

Usually, each part grows layer by layer in the form of a monolayer, and is regularly arranged into a long strip with a certain width.

Preferably, in the InAs/GaSb layer, along the direction in which the InAs portion and the GaSb portion are arranged, the width of the InAs portion is greater than the width of the GaSb portion;

The single material layer is InAs;

Preferably, the width of the GaSb portion is a monomolecular width.

Preferably, in the InAs/GaSb layer, along the direction in which the InAs portion and the GaSb portion are arranged, the width of the GaSb portion is greater than the width of the InAs portion;

The single substance layer is GaSb;

Preferably, the width of the InAs portion is a monomolecular width.

When the proportions of the two parts are different, the part of the material with a low proportion will be mixed into the part of the material with a high proportion, and the quantum wire embedding effect will be obtained. When the width of the material with a low proportion is only the width of a single molecule, the intercalation effect is most obvious, forming a similar point-hydrazine composite structure on the cross-section of the superlattice material.

Preferably, the quantum wire-embedded superlattice material further comprises a stepped substrate;

Preferably, the stepped substrate includes any one of a GaSb substrate, a GaAs substrate, an InAs substrate, an InP substrate and a Si substrate;

Preferably, the step inclination angle of the step-shaped substrate is 1-10°.

It should be noted that, the inclination angle of the step mentioned here does not mean that the step surface is inclined, but defines the ratio of the width to the height of the step.

Optionally, the step inclination angle of the step-shaped substrate may be 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, 9°, 10° and 1-10° any value in between.

A method for preparing a quantum wire-embedded superlattice material, comprising:

According to the structure of the quantum wire-embedded superlattice material, the InAs/GaSb layer and the single substance layer may be grown on the substrate in sequence.

Preferably, the growth method of GaSb comprises:

Turn on the Ga source and the Sb source, observe the coverage of GaSb on the substrate by high-energy electron diffraction, then turn off the Ga source and the Sb source, and simultaneously extract the residual Sb source in the reaction chamber to stop the growth of GaSb;

Preferably, the temperature of the substrate is 150-600° C., and the III/V beam current ratio is 1:(1-20);

Preferably, the growth method of InAs comprises:

Turn on the In source and the As source, observe the coverage of InAs on the substrate by high-energy electron diffraction, then turn off the In source and the As source, and simultaneously extract the residual As source in the reaction chamber to stop the growth of InAs.

Through the control of Ga and Sb sources and the extraction of residual source materials, growth down to the size of a monolayer can be achieved, resulting in quantum wire-embedded superlattice materials of different sizes.

Preferably, the migration time of GaSb and InAs on the steps of the substrate is less than or equal to 1s, and the migration speed is 0.5-1ML/s.

The control of the migration time and speed is to more accurately grow the superlattice material of the target size on the substrate.

An infrared band luminescent material, comprising the quantum wire-embedded superlattice material.

A detector includes the luminescent material in the infrared band.

Compared with the prior art, the beneficial effects of the present invention include:

The InAs/GaSb type II superlattice has too short minority carrier lifetime due to intrinsic Ga defects, which is not conducive to further improving the device performance. The quantum wire-embedded superlattice material provided by this application is the same as the traditional "quantum dot structure in a well". Since the quantum wire structure still has a strong quantum confinement effect, its phonon energy level is also split, and the quantum The wire has a long electron relaxation time, so the minority carrier lifetime can be extended by reducing the material dimension without changing the material. The luminous intensity of the material can be greatly improved, the gain capability of the active region and the absorption region based on this structure can be further improved, and the performance of the laser and the detector can be improved.

The preparation method of the quantum wire-embedded superlattice material provided by the present application adopts the layer-by-layer epitaxial growth mechanism based on molecular beam epitaxy (MBE) to obtain the superlattice material of the target structure, and the operation is simple.

The infrared band light-emitting material and detector provided by the present application are prepared by using the quantum wire-embedded superlattice material provided by the present application, and have obvious structural advantages and long infrared emission characteristics.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore do not It should be considered as limiting the scope of the invention.

1 is a schematic side view of the superlattice structure embedded with InAs quantum wires provided in Embodiment 1;

2 is a schematic diagram of the tilt angle of the substrate used in Example 1;

3 is a schematic side view of another superlattice structure embedded with InAs quantum wires provided in Embodiment 1;

FIG. 4 is a schematic right side view of the superlattice structure embedded with the InAs quantum wires shown in FIG. 3;

Fig. 5 is the structural schematic diagram, the HR-XRD spectrum of the x-axis and y-axis directions and the atomic force microscope image of the sample provided in Example 1;

Fig. 6 is the EDS mapping experiment result of the sample single element that embodiment 1 provides and the line scanning experiment result spectrum along the epitaxial direction;

Fig. 7 is the energy spectral line scanning experimental result of the sample provided in Example 1 and the HAADF image of the corresponding area;

FIG. 8 is a structural representation of the sample provided in Example 1, the TEM images in the x-direction and the y-direction, and the corresponding strain distribution images;

9 is a schematic diagram of a quantum wire-embedded superlattice structure provided in Embodiment 2;

10 is a schematic diagram of another quantum wire-embedded superlattice structure provided in Example 2;

11 is a schematic diagram of a quantum wire-embedded superlattice structure provided by Embodiment 3 and Embodiment 4;

12 is a schematic diagram of a superlattice structure provided by Comparative Example 1;

FIG. 13 shows the photoluminescence spectra of the superlattice materials obtained in Example 1 and Comparative Example 1. FIG.

Detailed ways

Terms as used herein:

"Prepared by" is synonymous with "comprising". As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article or device comprising the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such composition, step, method, article or device elements.

The conjunction "consisting of" excludes any unspecified element, step or component. If used in a claim, this phrase would make the claim closed to the exclusion of materials other than those described, but with the exception of conventional impurities associated therewith. When the phrase "consisting of" appears in a clause in the body of a claim rather than immediately following the subject matter, it is limited only to the elements described in that clause; other elements are not excluded from the description as a whole beyond the claims.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or a range bounded by a series of upper preferred values and lower preferred values, this should be understood as specifically disclosing any upper range limit or preferred value and any lower range limit or all ranges formed by any pairing of preferred values, whether or not the ranges are individually disclosed. For example, when a range "1-5" is disclosed, the described range should be construed to include the ranges "1-4", "1-3", "1-2", "1-2 and 4-5" , "1 to 3 and 5", etc. When numerical ranges are described herein, unless stated otherwise, the ranges are intended to include the endpoints and all integers and fractions within the range.

In these examples, unless otherwise indicated, the stated parts and percentages are by mass.

"Mass part" refers to a basic measurement unit that represents the mass ratio relationship of multiple components, and 1 part can represent any unit mass, such as 1 g, 2.689 g, and the like. If we say that the mass part of the A component is a part, and the mass part of the B component is b part, it means the ratio of the mass of the A component to the mass of the B component a:b. Or, the mass of the A component is aK, and the mass of the B component is bK (K is an arbitrary number, representing a multiplier factor). Unmistakably, unlike parts by mass, the sum of parts by mass of all components is not limited to 100 parts by mass.

"And/or" is used to indicate that one or both of the stated circumstances may occur, eg, A and/or B includes (A and B) and (A or B).

The embodiments of the present invention will be described in detail below in conjunction with specific examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. If the specific conditions are not indicated in the examples, it is carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used without the manufacturer's indication are conventional products that can be purchased from the market.

Example 1

As shown in FIG. 1 , this embodiment provides a superlattice structure in which InAs quantum wires are embedded. The superlattice structure embedded with InAs quantum wires includes an InAs/GaSb layer 1 and a single material layer 2. In the InAs/GaSb layer 1, the GaSb part 10 accounts for 80%, the InAs part 11 accounts for 20%, and the single material layer 2 is GaSb.

The thicknesses of the InAs/GaSb layer 1 and the single substance layer 2 are both 10ML.

Its preparation method is as follows:

The substrate 3 is a GaSb substrate with an inclination angle, the inclination angle is 2.86°, and the step width is about 6 nm. Growth parameters include: substrate temperature of 350 °C and III/V beam ratio of 1:1.

As shown in FIG. 2 , the inclination angle θ represents the ratio of the height to the width of the step surface.

Growth of InAs/GaSb Layer 1:

Firstly, the Ga source and Sb source were turned on, and the coverage of GaSb was observed by RHEED (High Energy Electron Diffraction). A 1ML thick GaSb is first grown on the substrate, and the migration time of GaSb on the substrate steps is controlled to be 0-1s, and the migration speed is 0.5ML/s. The coverage of the GaSb portion 10 on the steps reaches 80%, that is, 4.8 nm;

Following the cessation of growth of the GaSb portion, a 1ML thick InAs portion 11 is grown. First turn on the In source and the As source, observe the coverage of InAs by RHEED (High Energy Electron Diffraction), control the migration time of InAs on the substrate steps to be 0-1s, and the migration speed to be 0.5ML/s. After turning on for 1s, turn off the In source. and As source, and extract the residual As source in the reaction chamber at the same time to realize the growth stop of the InAs part 11; the coverage of the InAs part 11 on the steps reaches 20%, that is, 1.2 nm; GaSb coverage + InAs coverage = total steps length.

The above-mentioned growth process of the InAs/GaSb layer 1 was repeated 10 times to obtain 10 ML-thick InAs/GaSb layers 1 .

Growth of single substance layer 2:

First, the Ga source and the Sb source are turned on, and 10 MLs of GaSb are grown on the upper surface of the InAs/GaSb layer 1 . So far, one cycle of InAs/GaSb superlattice structure growth with InAs quantum wires embedded is completed.

As shown in FIG. 3 , in an optional embodiment, a quantum wire-embedded superlattice material may include a plurality of InAs/GaSb superlattice structures in which the single-period InAs quantum wires are embedded.

It can be seen from Fig. 3 (that is, the x-axis direction of Fig. 5 (a)) that the InAs portion with a thickness of 1ML is embedded in the GaSb portion with a width ratio of 20%; from the right side of the structure shown in Fig. 3, The layered structure shown in Figure 4 (ie, the y-axis direction of Figure 5 (a)) can be seen, and only the InAs part is displayed in the InAs/GaSb layer 1, that is, the InAs quantum wires are embedded in the GaSb layer.

The structural characteristics of the type II superlattice with embedded nanostructures obtained in Example 1 were analyzed and characterized, as shown in Figure 5, which is the high-resolution XRD (HR-XRD) spectrum and atomic force microscope image (AFM) of the sample. . Among them, (a) in FIG. 5 is a schematic structural diagram of the sample, which is grown on a substrate with a dip angle by means of monomolecular layer distribution epitaxy. When the sample is observed in the x direction, the InAs nanostructure can be seen in the cross section in this direction, similar to quantum dots, embedded in GaSb and periodic; when the sample is observed in the y direction, then in the The cross section in this direction can see the periodic InAs layer and GaSb layer, that is, the superlattice structure. This is the so-called type II superlattice structure with embedded nanostructures.

(b) and (c) in Figure 5 are the XRD spectra of the two directions, respectively. In the y-direction, typical superlattice diffraction peaks can be observed due to the existence of the superlattice structure. Similar to the normalized diffraction peaks of the planar InAs/GaSb system superlattice and the InAs/InAsSb system superlattice, in Figure 5(b), the sample shows strong diffraction peaks and clearly visible satellite diffraction peaks. The diffraction peak reached the 3rd order, which indicated that the sample had good crystal quality. The 0th order diffraction peak does not coincide with the substrate peak, indicating that there is a certain mismatch between the epitaxial structure and the substrate. On the XRD spectrum in the other direction, only the diffraction peaks of the epitaxial material can be observed, and no satellite peaks can be observed. It shows that there is no periodic distribution of superlattice in this direction. In the corresponding AFM results, the surface roughness and surface morphology are also quite different from the completely planar superlattices.

The samples were subjected to energy spectrum analysis, and the distribution states of all elements and single elements were shown in Figure 6 (HAADF-STEM and EDS tests were performed on the cross-sectional area of the sample). The area on the left (shown in blue) is the GaSb substrate, where In, As, Ga and Sb can be observed in the epitaxial layers. For the distribution of single elements, it can be seen that the four elements of In, As, Ga and Sb are uniformly distributed in the sample. Ga and Sb are not present in the epitaxial layer. Especially on the mapping images of As and Ga, a strip-like distribution can be observed.

Fig. 7 is the HAADF image in the box interval of Fig. 6. In the HAADF image, the morphology of the superlattice can be seen, and there is an obvious interface structure. The average content distribution of all elements can be obtained in the epitaxial growth direction. As shown in Figure 7, the proportion of In and As elements is significantly lower than that of Ga and Sb, and the proportion of In and As in the sample is almost the same, about 13%. . There are also periodic changes. The ratio of Ga to Sb is also close to 1:1, which is about 25% in the whole sample, so we can calculate that the ratio of In to Ga in the InAs nanostructure embedded type II superlattice sample is about 1:2 , in line with the epitaxy design results.

In order to clarify the characteristics of the special structure of this quantum wire-embedded superlattice, HRTEM tests and characterizations were carried out, as shown in Figure 8. Fig. 8(a) is a schematic diagram of a substrate with a tilt angle and embedded nanostructured superlattice, and Fig. 8(b) and (c) are TEM images and corresponding strain distribution images in different directions, respectively. εxx is the strain component parallel to the direction of the superlattice interface, εyy is the direction perpendicular to the superlattice interface, and the GaSb substrate is selected as the reference frame for these two strain components. In the HRTEM image, the layer-by-layer distribution image unique to the superlattice can be clearly seen, in which the dark line in Fig. 8(b) is the InAs nanostructure, and the slightly brighter area is the GaSb part. In (c) of Fig. 8, we can observe the morphology of QD embedded, although the QD morphology is not very clear. After transformation by the GPA method, the same as the planar superlattice, GaSb and InAs are embodied in the compressive region (shown in red) and the tensile region (shown in blue-green), respectively. In the εxx direction, due to the small size of the nanowires, the lateral arrangement of the nanowires can be observed on the strain diagram. The line-to-line spacing matches the width of the GaSb portion in the TEM image. In the εyy direction, since there is no strain, there is no obvious change in the strain. On the other hand, in (c) of FIG. 8 , since the quantum dots are embedded in GaSb, the distance between dots is not large. Therefore, in the εxx direction, a strain image similar to that generated after the nanowire is embedded is also presented. In the εyy direction, a blue-green stretched region can be clearly observed, similar to the shape of quantum dots. Therefore, the TEM test results further verify that the structure we designed really exists.

In order to study the optical properties of this special superlattice structure, we also carried out low-temperature PL spectroscopy at 77K. Figure 9 presents the PL spectrum of the sample. All these superlattices have long-infrared emission characteristics, and it can be seen that the luminescence peak of the samples is located at 5.6 μm, which is caused by the micro-band gap emission of the superlattices. Since this sample is still a Ga-containing superlattice system, the minority carrier lifetime is short. And there are defects in the sample, so the luminous intensity is relatively high. But the luminescence in this band can still indicate that this is a special InAs/GaSb class II superlattice material with embedded nanowires.

Example 2

Referring to FIG. 1 , this embodiment provides a superlattice structure in which InAs quantum wires are embedded. The superlattice structure in which the InAs quantum wires are embedded includes an InAs/GaSb layer 1 and a single material layer 2. In the InAs/GaSb layer 1, the GaSb part 10 accounts for 90%, the InAs part 11 accounts for 10%, and the single material layer 2 is GaSb.

The thicknesses of the InAs/GaSb layer 1 and the single substance layer 2 are both 20ML.

Its preparation method is as follows:

The substrate 3 is a GaSb substrate with an inclination angle, the inclination angle is 2.86°, and the step width is about 6 nm. Growth parameters include: substrate temperature of 550 °C and III/V beam ratio of 1:5.

In other embodiments, the tilt angle of the substrate may be between 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, 9°, 10°, etc. 1-10 any value.

Growth of InAs/GaSb Layer 1:

Firstly, the Ga source and Sb source were turned on, and the coverage of GaSb was observed by RHEED (High Energy Electron Diffraction). A 1ML thick GaSb is first grown on the substrate, and the migration time of GaSb on the substrate steps is controlled to be 0-1s, and the migration speed is 0.5ML/s. The coverage of the GaSb portion 10 on the steps reaches 90%, that is, 5.4 nm;

Following the cessation of growth of the GaSb portion, a 1ML thick InAs portion 11 is grown. First turn on the In source and As source, observe the coverage of InAs by RHEED (High Energy Electron Diffraction), control the migration time of InAs on the substrate steps to be 0-1s, and the migration speed to be 0.5ML/s. After turning on for 1s, turn off the In source. and the As source, and extract the residual As source in the reaction chamber at the same time to stop the growth of the InAs part 11; the coverage of the InAs part 11 on the steps reaches 10%, that is, 0.6 nm; GaSb coverage + InAs coverage = total steps length.

The above-mentioned growth process of the InAs/GaSb layer 1 was repeated 20 times to obtain 20 ML-thick InAs/GaSb layers 1 .

Growth of single substance layer 2:

First, the Ga source and the Sb source are turned on, and 20 MLs of GaSb are grown on the upper surface of the InAs/GaSb layer 1 . So far, one cycle of InAs/GaSb superlattice structure growth with InAs quantum wires embedded is completed.

In an alternative embodiment, the thicknesses of the InAs/GaSb layer 1 and the single substance layer 2 may be unequal. For example, as shown in FIG. 9 , the InAs/GaSb layer 1 may be 20ML (it should be noted that in FIG. 9 , the dividing line of the InAs/GaSb layer 1 is only for illustration), and the single substance layer 2 is 10ML.

Optionally, as shown in FIG. 10 , the InAs/GaSb layer 1 may be 10ML, and the single substance layer 2 may be 20ML (it should be noted that the dividing line of the single substance layer 2 in FIG. 10 is for illustration only).

Example 3

As shown in FIG. 11 , this embodiment provides a superlattice structure in which GaSb quantum wires are embedded. The superlattice structure embedded with GaSb quantum wires includes an InAs/GaSb layer 1 and a single material layer 2. In the InAs/GaSb layer 1, the InAs portion 11 accounts for 90%, the GaSb portion 10 accounts for 10%, and the single material layer 2 is InAs.

The thicknesses of the InAs/GaSb layer 1 and the single substance layer 2 are both 10ML.

Its preparation method is as follows:

The substrate 3 is a GaSb substrate with an inclination angle, the inclination angle is 2.86°, and the step width is about 6 nm. Growth parameters include: substrate temperature of 150 °C and III/V beam ratio of 1:3.

In other embodiments, the substrate 3 may be any one of a GaAs substrate, an InAs substrate, an InP substrate and a Si substrate.

Growth of InAs/GaSb Layer 1:

First turn on the In source and the As source, observe the coverage of InAs by RHEED (High Energy Electron Diffraction), control the migration time of InAs on the substrate steps to be 0-1s, and the migration speed to be 0.5ML/s. After turning on for 1s, turn off the In source. and the As source, while extracting the residual As source in the reaction chamber to stop the growth of the InAs portion 11; the coverage of the InAs portion 11 on the steps reaches 90%, that is, 5.4 nm.

After the InAs part 11 stops growing, the Ga source and Sb source are turned on, and the coverage of GaSb is observed by RHEED (High Energy Electron Diffraction). Growth of the GaSb layer is stopped. A 1ML thick GaSb is first grown on the substrate, and the migration time of GaSb on the substrate steps is controlled to be 0-1s, and the migration speed is 0.5ML/s. The coverage of the GaSb portion 10 on the steps reaches 10%, that is, 0.6 nm; GaSb coverage+InAs coverage=total step length.

The above-mentioned growth process of the InAs/GaSb layer 1 was repeated 10 times to obtain 10 ML-thick InAs/GaSb layers 1 .

Growth of single substance layer 2:

First, the In source and the As source are turned on, and 10 MLs of InAs are grown on the upper surface of the InAs/GaSb layer 1 . So far, one cycle of InAs/GaSb superlattice structure growth with InAs quantum wires embedded is completed.

Example 4

Referring to FIG. 11 , this embodiment provides a superlattice structure embedded with GaSb quantum wires. The superlattice structure embedded with GaSb quantum wires includes an InAs/GaSb layer 1 and a single material layer 2. In the InAs/GaSb layer 1, the InAs portion 11 accounts for 80%, the GaSb portion 10 accounts for 20%, and the single material layer 2 is InAs.

The thicknesses of the InAs/GaSb layer 1 and the single substance layer 2 are both 10ML.

Its preparation method is as follows:

The substrate 3 is a GaSb substrate with an inclination angle, the inclination angle is 2.86°, and the step width is about 6 nm. Growth parameters include: substrate temperature of 350 °C and III/V beam ratio of 1:10.

Growth of InAs/GaSb Layer 1:

First turn on the In source and the As source, observe the coverage of InAs by RHEED (High Energy Electron Diffraction), control the migration time of InAs on the substrate steps to be 0-1s, and the migration speed to be 0.5ML/s. After turning on for 1s, turn off the In source. and the As source, while extracting the residual As source in the reaction chamber to stop the growth of the InAs portion 11; the coverage of the InAs portion 11 on the steps reaches 80%, that is, 4.8 nm.

After the growth of the InAs part 11 was stopped, the Ga source and Sb source were turned on, and the coverage of GaSb was observed by RHEED (High Energy Electron Diffraction). Growth of the GaSb layer is stopped. A 1ML thick GaSb is first grown on the substrate, and the migration time of GaSb on the substrate steps is controlled to be 0-1s, and the migration speed is 0.5ML/s. The coverage of the GaSb portion 10 on the steps reaches 20%, that is, 1.2 nm; GaSb coverage+InAs coverage=total step length.

The above-mentioned growth process of the InAs/GaSb layer 1 was repeated 10 times to obtain 10 ML-thick InAs/GaSb layers 1 .

Growth of single substance layer 2:

First, the In source and the As source are turned on, and 10 MLs of InAs are grown on the upper surface of the InAs/GaSb layer 1 . So far, one cycle of InAs/GaSb superlattice structure growth with InAs quantum wires embedded is completed.

When multiple periods of quantum wire-embedded InAs/GaSb superlattice structure materials are required, the above steps can be repeated to complete the structure growth of each period one by one.

Comparative Example 1

As shown in FIG. 12 , in a common InAs/GaSb superlattice structure, the widths of the InAs portion and the GaSb portion are equal, and no single material layer is provided.

The photoluminescence spectra of the superlattice materials of Example 1 and Comparative Example 1 obtained by testing are shown in FIG. 13 .

It can be seen from Figure 13 that the photoluminescence spectrum (PL) data of the quantum dot-embedded superlattice material sample in Example 1 shows that its luminescence intensity is significantly stronger than that of the ordinary InAs/GaSb superlattice, which is precisely due to the InAs/GaSb superlattice. Quantum structuring of the InAs moiety in the GaSb superlattice extends the minority carrier lifetime. Finally, the luminous intensity of the material is improved.

The quantum wire-embedded superlattice material provided by the present application can be used to prepare a luminescent material in the infrared band, and further to prepare a detector.

The quantum wire-embedded superlattice material provided by the present application introduces quantum dot structure into the quantum well, and utilizes the "phonon bottleneck" effect of quantum dots, that is, due to the quantum confinement effect, the phonon energy level of quantum dots and the electron's The energy levels are equally divided. The electrons in the excited state must couple with the phonon to release a certain amount of energy before relaxing to the ground state, and relax to the bottom of the conduction band. Because the energy of its phonon is fixed, it is difficult to couple to the bulk material in a short time. With suitable phonons, the electrons in the quantum dots have a longer relaxation time, which is beneficial to improve the quantum efficiency of the material, thereby improving the performance of the device.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. scope.

Furthermore, it will be understood by those skilled in the art that although some of the embodiments herein include certain features, but not others, included in other embodiments, that combinations of features of the different embodiments are intended to be within the scope of the present invention And form different embodiments. For example, in the above claims, any of the claimed embodiments may be used in any combination. The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Claims (11)

1. a superlattice material embedded in quantum wire, it is characterized in that, comprise at least one InAs/GaSb layer and at least one single material layer that stack is arranged; Described InAs/GaSb layer comprises InAs part and GaSb part, described single The material layer includes InAs or GaSb; The InAs portion and the GaSb portion are alternately arranged in the InAs/GaSb layer and have different widths along the direction of the arrangement; The composition of at least one of the single material layers in the quantum wire-embedded superlattice structure is the same as the composition of a large portion of the adjacent InAs/GaSb layer; Each of the InAs portion and the GaSb portion has a rectangular parallelepiped shape; In the InAs/GaSb layer, along the direction in which the InAs part and the GaSb part are arranged, the width of the InAs part is greater than the width of the GaSb part; the single substance layer is InAs; The width is the monomolecular width; or, In the InAs/GaSb layer, along the direction in which the InAs part and the GaSb part are arranged, the width of the GaSb part is greater than the width of the InAs part; the single substance layer is GaSb; The width is the monomolecular width. 2 . The quantum wire-embedded superlattice material according to claim 1 , further comprising a stepped substrate. 3 . 3. The quantum wire-embedded superlattice material according to claim 2, wherein the stepped substrate comprises a GaSb substrate, a GaAs substrate, an InAs substrate, an InP substrate and a Si substrate. either. 4 . The quantum wire-embedded superlattice material according to claim 2 , wherein the step inclination angle of the stepped substrate is 1-10°. 5 . 5. the preparation method of the superlattice material embedded quantum wire described in any one of claim 1-4, is characterized in that, comprising: According to the structure of the quantum wire-embedded superlattice material, the InAs/GaSb layer and the single substance layer may be grown on the substrate in sequence. 6. preparation method according to claim 5, is characterized in that, the growth method of GaSb comprises: Turn on the Ga source and Sb source, observe the coverage of GaSb on the substrate by high-energy electron diffraction, then turn off the Ga source and the Sb source, and extract the residual Sb source in the reaction chamber to stop the growth of GaSb. 7 . The preparation method according to claim 5 , wherein the temperature of the substrate is 150-600° C., and the III/V beam current ratio is 1:(1-20). 8 . 8. preparation method according to claim 5 is characterized in that, the growth method of InAs comprises: Turn on the In source and the As source, observe the coverage of InAs on the substrate by high-energy electron diffraction, then turn off the In source and the As source, and simultaneously extract the residual As source in the reaction chamber to stop the growth of InAs. 9 . The preparation method according to claim 5 , wherein the migration time of GaSb and InAs on the steps of the substrate is less than or equal to 1s, and the migration speed is 0.5-1ML/s. 10 . 10 . An infrared band light-emitting material, characterized in that it comprises the quantum wire-embedded superlattice material according to any one of claims 1 to 4 . 11 . 11. A detector, characterized in that it comprises the luminescent material in the infrared band according to claim 10.

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