CN108988125A - In infrared superlattices band-to-band transition laser and preparation method thereof - Google Patents

Abstract

A mid-infrared superlattice interband transition laser, comprising: a substrate, which is an N-type gallium-antimony material; a lower confinement layer, which is prepared on the substrate, and is N-type doped AlGaAsSb; a lower waveguide layer, which is prepared on the lower confinement layer. The upper layer is non-doped AlGaInAsSb; the active region is prepared on the lower waveguide layer and is a superlattice interband transition active region, and the active region includes: an InAs/AlSb superlattice for transporting electrons; and the InGaSb/AlSb superlattice for transporting holes; the upper waveguide layer, prepared on the active region, is non-doped AlGaInAsSb; the upper confinement layer, prepared on the upper waveguide layer, is P-type doped AlGaAsSb; and The upper contact layer, prepared on the upper confinement layer, is P-type doped GaSb; the laser can alleviate the problem that the long-wavelength band of the quantum well laser is easily limited by Auger recombination, and the interband cascade laser uses W-type The structure of the active region leads to a small gain, and its own limited effect on electrons and holes makes it difficult to achieve short-wavelength work and other technical problems.

Description

Mid-infrared superlattice interband transition laser and its preparation method

technical field

The present disclosure relates to the field of mid-infrared semiconductor lasers, in particular to a mid-infrared superlattice interband transition laser and a preparation method thereof.

Background technique

The 2-5μm band contains a very important atmospheric window. Asymmetric atoms and polyatomic molecular gases have strong absorption peaks in the 2-5um band. For example, water molecules have a strong absorption peak at 2.7um, and methane CH ₄ in There is an absorption peak at 3.41um, and hydrogen chloride gas HCl has an absorption peak at 3.54um. This characteristic is an inherent property of the infrared active substance itself. For example, in the 2-2.5μm band, water vapor absorbs very weakly, and some polluting gases, such as C0, CH ₄ , NO ₂ , have particularly strong absorption, so they are very suitable for environmental monitoring. Compared with other gas detection technologies, mid-infrared laser gas detection technology has a series of advantages: wide measurement range, wavelength covering mid-infrared band; high detection accuracy; fast response speed, real-time online measurement; good selectivity, single output wavelength , high tuning precision, free from background gas interference; can realize open measurement with long optical path. Absorption spectroscopy (TDLAS) and photoacoustic spectroscopy (PAS) based on mid-infrared lasers have broad application prospects in the fields of industrial gas online analysis, environmental monitoring, and breath detection. In addition, in the military field, the current infrared guided missiles have developed from the first-generation homing guidance to the fourth-generation 2-5um band mid-infrared band staring imaging guidance. This technology greatly improves the sensitivity and The anti-interference ability makes it have a longer attack distance, and greatly reduces the effectiveness of some traditional infrared countermeasures such as flash lights and infrared jamming bombs, which poses a great threat in war. The most effective way to deal with it is based on the 2-5μm mid-infrared semiconductor laser countermeasure weapon system, which can make the focal plane array detector in the guidance system blind and invalid, or even completely physically destroy it. In addition, lasers in this band can also be used in free space optical communication. The free space optical communication system uses the atmosphere as the transmission medium for optical signal transmission, which is highly directional, highly invisible, and highly confidential. The lasing wavelength of the mid-to-far infrared semiconductor laser covers the two atmospheric windows of 2-5μm and 8-13μm, which can be used as an optical transmitter for communication, greatly reducing the impact of severe weather such as smog and improving stability. At the same time, free space communication does not require the laying of optical fiber networks, and can communicate over long distances, such as satellite-to-earth communication.

At present, lasers that can realize the mid-infrared band mainly include GaSb-based quantum well lasers, GaSb-based quantum well cascade lasers, and GaSb inter-band cascaded lasers. It is easy to be limited by Auger recombination, and it is difficult to achieve lasing in a longer wavelength band. Because of the W-type active region structure, it is difficult to achieve particle population inversion in interband cascaded lasers, and its own for electrons and holes. The weak confinement effect makes it more difficult to achieve short-wavelength work.

public content

(1) Technical problems to be solved

The present disclosure provides a mid-infrared superlattice interband transition laser and its preparation method to alleviate the problem that the long wavelength band of quantum well lasers in the prior art is easily limited by Auger recombination, and the interband cascade laser adopts The W-type active region structure leads to a small gain, and its own weak confinement effect on electrons and holes makes it difficult to achieve short-wavelength work and other technical problems.

(2) Technical solutions

The disclosure provides a mid-infrared superlattice interband transition laser, including: a substrate, which is an N-type gallium-antimony material; a lower confinement layer prepared on the substrate, which is N-type doped AlGaAsSb; a lower waveguide layer, prepared On the lower confinement layer, it is non-doped AlGaInAsSb; the active region, prepared on the lower waveguide layer, is the superlattice interband transition active region, including: InAs/AlSb superlattice for transporting electrons; and InGaSb/AlSb superlattice for transporting holes; the upper waveguide layer, prepared on the active region, is undoped AlGaInAsSb; the upper confinement layer, prepared on the upper waveguide layer, is P-type doped AlGaAsSb; and the upper contact layer, prepared on the upper confinement layer, is P-type doped GaSb.

In the embodiment of the present disclosure, the period of the InAs/AlSb superlattice for transporting electrons is 3-9 periods, the thickness of InAs is gradually changed in the superlattice, and the thickness is 1-3.5nm, and the thickness of AlSb is 1-3.5nm. 2nm.

In the embodiment of the present disclosure, in the InGaSb/AlSb superlattice for transporting holes, the thicknesses of InGaSb and AlSb are gradually changed, and the period is 1-4 periods, and the In composition in the InGaSb hole well is 0.25- 0.4, the thickness of the InGaSb hole well is 1-4nm, and the thickness of AlSb is 1-2nm.

In an embodiment of the present disclosure, the lower confinement layer is an N-type doped AlGaAsSb material, its composition ratio is Al _0.6-0.9 GaAs _0.02-0.04 Sb, and the tellurium doping concentration is 1e ¹⁷ -1e ¹⁸ em ^-3 , the thickness is 1.0μm-2μm.

In the embodiment of the present disclosure, the lower waveguide layer is made of non-doped aluminum gallium indium arsenic antimony material, the composition ratio is Al _{0.1-0.3 GaIn 0.2-0.4} As _0.15-0.35 Sb, and the thickness is 300nm-600nm.

In an embodiment of the present disclosure, the upper waveguide layer is a P-type doped AlGaInAsSb material, its composition ratio is Al _0.1-0.3 GaIn _0.2-0.4 As _0.15-0.35 Sb, and its thickness is 300nm-600nm.

In the embodiment of the present disclosure, the upper confinement layer is a P-type doped AlGaAsSb material, its composition ratio is Al _0.3-0.9 GaAs _0.02-0.04 Sb, and the beryllium doping concentration is 1e ¹⁸ -1e ¹⁹ cm ^-3 , the thickness is 1.0μm-2μm.

In an embodiment of the present disclosure, the upper contact layer is a P-type doped gallium-antimony material with a beryllium doping concentration of 1e ¹⁹ -8e ¹⁹ cm ^-3 and a thickness of 250nm-500nm.

In another aspect of the present disclosure, a preparation method is provided for preparing the mid-infrared superlattice interband transition laser described in any one of the above, including: Step A: preparing the mid-infrared superlattice interband transition laser the epitaxial wafer; step B: prepare the ridge waveguide of the laser on the epitaxial wafer prepared in step A; step C: deposit an insulating layer on the surface of the epitaxial wafer after preparing the ridge waveguide in step B; step D: in step C On the basis, etching the insulating layer above the corresponding ridges to prepare electrode windows; step E, preparing p-type front electrodes above the electrode windows prepared in step D;

Step F, prepare an n-type back electrode on the back of the substrate; Step G, dissociate the sheet into bars, and coat a film on the dissociated surface of the bars; and Step H, dissociate the tube core, flip chip soldering sinking, thus making a mid-infrared superlattice interband transition laser.

In an embodiment of the present disclosure, the material of the insulating layer in step C includes: SiO ₂ or Si ₃ N ₄ .

(3) Beneficial effects

It can be seen from the above technical solutions that the mid-infrared superlattice interband transition laser and its preparation method of the present disclosure have at least one or part of the following beneficial effects:

(1) The transition of electrons occurs in the interband transition of two superlattices. This mechanism can ensure a huge population inversion under bias voltage;

(2) Due to the limiting effect of the superlattice itself, there will be strong restrictions on electrons and holes, which can ensure the effective use of electrons and holes;

(3) Since the interband transition mechanism of superlattice is similar to interband radiative recombination, the generation of Auger recombination can be effectively reduced in the longer wavelength band of mid-infrared;

(4) It can effectively improve the gain of the active area;

(5) The wavelength can be effectively adjusted by changing the width of the well in the superlattice.

Description of drawings

1 is a schematic diagram of the epitaxial structure of a mid-infrared superlattice interband transition laser in an embodiment of the present disclosure;

Fig. 2 is an energy band diagram of a superlattice interband transition active region of a mid-infrared superlattice interband transition laser according to an embodiment of the present disclosure.

3 is a photoluminescent spectrum (PL spectrum) of the superlattice interband transition active region of the mid-infrared superlattice interband transition laser according to an embodiment of the present disclosure.

FIG. 4 is a process flow diagram of a mid-infrared superlattice interband transition laser according to an embodiment of the present disclosure.

FIG. 5 is a schematic diagram of steps in a method of manufacturing a mid-infrared superlattice interband transition laser according to an embodiment of the present disclosure.

[Description of main component symbols of the embodiment of the present disclosure in the accompanying drawings]

100-substrate; 200-lower confinement layer; 300-lower waveguide layer;

400 - active area;

410-InAs/AlSb superlattice; 420-InGaSb/AlSb superlattice;

500-upper waveguide layer; 600-upper confinement layer; 700-upper contact layer.

Detailed ways

The present disclosure provides a mid-infrared superlattice interband transition laser and a preparation method thereof, the laser adopts an interband transition mechanism in which an electron transported in a superlattice transitions to a hole state in another superlattice , this method of interband transition can effectively increase the population inversion in the active region, increase the gain of the laser, and adjust the lasing wavelength of the device by adjusting the width of the well in the superlattice. In addition, it can also effectively Suppressing the generation of Auger recombination at long wavelengths enables the device to work in a larger wavelength range and realize the work in the mid-infrared band. Adopting this structure can greatly improve the gain of the active region and the performance of the laser.

In the embodiment of the present disclosure, the mid-infrared superlattice interband transition laser emits light recombinedly through the transition of electrons in the superlattice to holes, and this laser can be changed by adjusting the thickness of the InAs layer in the superlattice wavelength, and the superlattice structure itself has a strong restriction on electrons, the formation of microstrips in the superlattice under bias can ensure the almost unimpeded transmission of electrons, which is conducive to the inversion of the number of particles. In addition, the structure of the second-type superlattice with interband transition can effectively reduce the Auger recombination rate. Therefore, the disclosed mid-infrared superlattice interband transition structure laser can effectively improve the gain of the active region, conveniently adjust the working wavelength of the laser, and have higher laser performance.

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

In the present disclosure, a mid-infrared superlattice interband transition laser is provided, and FIG. 1 is a schematic diagram of the epitaxial structure of the laser, as shown in FIG. 1 , the epitaxial structure of the mid-infrared superlattice interband transition laser, include:

The substrate 100 is an N-type GaSb material;

The lower confinement layer 200, prepared on the substrate 100, is N-type doped AlGaAsSb;

The lower waveguide layer 300, prepared on the lower confinement layer 200, is non-doped AlGaInAsSb;

The active region 400, prepared on the lower waveguide layer 300, is an active region for transition between superlattice bands;

The upper waveguide layer 500, prepared on the active region 400, is non-doped AlGaInAsSb;

The upper confinement layer 600, prepared on the upper waveguide layer 500, is P-type doped AlGaAsSb; and

The upper contact layer 700, prepared on the upper confinement layer 600, is P-type doped GaSb.

In an embodiment of the present disclosure, FIG. 2 is an energy band diagram of a superlattice interband transition active region of a mid-infrared superlattice interband transition laser. As shown in FIG. 2 , the active region 400 includes: An InAs/AlSb superlattice 410 for transporting electrons; and an InGaSb/AlSb superlattice 420 for transporting holes.

In the InAs/AlSb superlattice 410 for transporting electrons, the thickness of InAs is gradually changed, and the thickness is about 1-3.5 nm, while the thickness of AlSb is about 1-2 nm.

In the embodiment of the present disclosure, the InAs/AlSb superlattice 410 for transporting electrons basically has 3-9 periods, and the thickness of InAs gradually changes in the superlattice, so as to ensure the microband of the superlattice under voltage Keeping the level, by adjusting the thickness of InAs, a laser in the mid-infrared band of 2-5um can be realized.

In the embodiment of the present disclosure, the hole-transporting InGaSb/AlSb superlattice 420, in which the thickness of InGaSb and AlSb is gradually changed, so as to ensure that the hole energy level remains at the same level under the voltage, and its period is 1-4 Period, wherein the In composition in the InGaSb hole well is between 0.25-0.4 to ensure sufficient hole confinement, wherein the thickness of the InGaSb hole well is 1-4 nm, and the thickness of the AlSb is about 1 -2nm, the lasing wavelength can be adjusted by adjusting the InGaSb hole well and the In composition.

In an embodiment of the present disclosure, the lower confinement layer 200 is an N-type doped AlGaAsSb material, its composition ratio is Al _0.6-0.9 GaAs _0.02-0.04 Sb, and the tellurium doping concentration is 1e ¹⁷ -1e ¹⁸ cm ^-3 , the thickness is 1.0μm-2μm.

In the embodiment of the present disclosure, the lower waveguide layer 300 is made of non-doped AlGaInAsSb material, the composition ratio is Al _0.1-0.3 GaIn _0.2-0.4 As _0.15-0.35 Sb, and the thickness is 300nm-600nm.

In the embodiment of the present disclosure, the upper waveguide layer 500 is a P-type doped aluminum gallium indium arsenic antimony material, its composition ratio is Al _0.1-0.3 GaIn _0.2-0.4 As _0.15-0.35 Sb, and the thickness is 300nm-600nm .

In the embodiment of the present disclosure, the upper confinement layer 600 is a P-type doped aluminum gallium arsenic antimony material, its composition ratio is Al _0.3-0.9 GaAs _0.02-0.04 Sb, and the beryllium doping concentration is 1e ¹⁸ -1e ¹⁹ cm ^-3 , the thickness is 1.0μm-2μm.

In an embodiment of the present disclosure, the upper contact layer 700 is a P-type doped gallium-antimony material with a beryllium doping concentration of 1e ¹⁹ -8e ¹⁹ cm ^-3 and a thickness of 250nm-500nm.

In the embodiment of the present disclosure, the active region of the mid-infrared superlattice interband transition laser adopts a new type of transition mechanism, which is different from the one-type or two-type quantum well transition in ordinary lasers. , this transition is completed in the superlattice InAs/AlSb that binds electrons and the superlattice InGaSb/AlSb that binds holes. Since this transition is not performed in one material, it is essentially a Interband transition, Figure 2 is the energy band diagram of the superlattice interband transition active region of the mid-infrared superlattice interband transition laser, as shown in Figure 2, the active region includes the superlattice InAs/ AlSb, the thickness of InAs in this superlattice is gradually changed, the thickness is about 1-3.5nm, and the thickness of AISb is about 1-2nm, this superlattice is basically in 3-9 periods, the thickness of InAs is gradually changed in the super lattice, to This ensures that the microstrip of the superlattice remains horizontal under voltage. By adjusting the thickness of InAs, a 2-5um laser in the mid-infrared band can be realized. The superlattice InGaSb/AlSb superlattice that transports holes in the quantum well is also the same. The thickness of the superlattice is gradually changed, so as to ensure that the hole energy level remains at the same level under the voltage, and its period is 1-4 periods. Hole confinement, where the thickness of the InGaSb hole well is 1-4nm, and the thickness of AlSb is about 1-2nm, the lasing wavelength can be adjusted by adjusting the InGaSb hole well and the In composition, and the InAs/AlSb superlattice mainly It is the upper energy state E _e of electrons, and the lower energy state E _h of holes in the InGaSb/A1Sb superlattice. The recombination of electrons and holes occurs before the two superlattices, which is an oblique transition between bands. This interband transition mechanism can effectively suppress the Auger recombination rate in the longer band. The interband transition mechanism proposed in the present disclosure can effectively use the forward bias voltage of the pn junction to generate population inversion and increase the gain. And the wavelength of the entire mid-infrared band can be adjusted conveniently. It has good device performance, as shown in Figure 3, which is the photoluminescent spectrum of the active region of the mid-infrared superlattice interband transition laser at mid-infrared 3621nm.

In the embodiment of the present disclosure, the mid-infrared superlattice interband transition laser adopts a ridge waveguide structure, but the present disclosure is not limited thereto. Those skilled in the art should be quite clear that the waveguide structure in the laser can also be a double-channel ridge waveguide structure. In the embodiment of the present disclosure, the depth of the ridge waveguide structure formed by etching can be any position below the upper surface of the AlGaAsSb upper confinement layer and above the lower surface of the AlGaInAsSb upper waveguide layer, and the width of the double-channel ridge waveguide can be narrow strip type 5 -35um, for a strip-shaped waveguide structure with a single structure, it can be a wide strip of about 100-200um. Those skilled in the art should be clear that there can be a variety of specific waveguide structures in this example, and this is not the main focus of discussion .

In the present disclosure, a preparation method is also provided for preparing the mid-infrared superlattice interband transition laser, FIG. 4 is a process flow diagram of the preparation method, and FIG. 5 is a schematic diagram of the steps of the preparation method, combined with Shown in Fig. 4 and Fig. 5, described preparation method comprises:

Step A: preparing epitaxial wafers for mid-infrared superlattice interband transition lasers;

Specifically, the GaSb substrate is placed in the molecular beam epitaxy equipment, and the lower confinement layer, the lower waveguide layer, the superlattice interband transition active region, the upper waveguide layer, the upper confinement layer, and the upper contact layer are sequentially prepared, that is, the GaSb substrate An Al _0.85 Ga _0.15 As _0.07 Sb _0.93 lower confinement layer 200 with a doping concentration of 5e ¹⁷ epitaxially doped with Te on the bottom, with a thickness of about 1.5um; afterward epitaxial undoped Al _0.20 Ga _0.55 In _0.25 As _0.33 Sb _0.67 lower waveguide Layer 300 with a thickness of about 400nm; followed by epitaxy of 5 pairs of InAs/AlSb and 4 pairs of In _0.35 Ga _0.65 Sb/AlSb superlattice interband transition active region; and then epitaxy of 400nm undoped Al _0.20 Ga _0.55 In _0.25 As _0.33 Sb _0.67 upper waveguide layer; and Al _0.85 Ga _0.15 As _0.07 Sb _0.93 upper confinement layer doped with Be and with a doping concentration of 5e ¹⁷ ; finally an epitaxial GaSb upper contact layer doped with Be and heavily doped with a concentration of 5e ¹⁸ .

Step B: preparing the ridge waveguide of the laser on the epitaxial wafer prepared in step A, including:

Sub-step B1 _: Spin-coat photoresist on the upper contact layer, use a common contact exposure method, use a photolithography plate as a mask, and prepare a mask pattern of the ridge waveguide, the entire pattern is located on the upper surface of the device; and

Sub-step B ₂ : use photoresist as a mask, and etch the upper surface by inductively coupled plasma (ICP), so as to obtain a ridge waveguide.

Step C: Depositing an insulating layer on the surface of the epitaxial wafer after the ridge waveguide is prepared;

A plasma-enhanced chemical vapor deposition (PECVD) method is used to deposit an insulating layer with a thickness of 250-300nm, and the material of the insulating layer includes: SiO ₂ or Si ₃ N ₄ ;

Step D: On the basis of step C, etch the insulating layer above the corresponding ridges to prepare electrode windows.

Using contact lithography, use a photolithography plate as a mask above the ridge waveguide to prepare the electrode window pattern above the ridge waveguide, then use photoresist as a mask, and use ICP to etch the 250nm insulating layer to make the device P The type contact layer is exposed for subsequent metal electrodes to form ohmic contacts.

Step E, preparing a p-type front electrode above the electrode window prepared in step D.

Ti/Pu/Au is sputtered to a thickness of 20/50/300 nm on the upper surface of the device by magnetron sputtering to form an ohmic contact on the P surface.

Step F, preparing an n-type back electrode on the back of the substrate.

Thinning and polishing the lower surface of the device, thinning the GaSb substrate of the device to 150-200um, and polishing; then using Ni/AuGe/Au to form an ohmic contact on the N surface with a thickness of 5/100/300nm, and then Put it into a rapid thermal annealing (RTP) equipment for annealing, so as to form an ohmic contact on the N side.

Step G, dissociate the sheet into strips, and coat the dissociated surfaces of the strips;

Antireflection coating λ/4 Al ₂ O ₃ is coated on the front cavity, and 200nm Al ₂ O ₃ /100nm Au is coated on the back cavity.

Step H, dissociate the tube core, and flip-chip solder it on the heat sink, so as to manufacture a mid-infrared superlattice interband transition laser.

So far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. It should be noted that, in the accompanying drawings or in the text of the specification, implementations that are not shown or described are forms known to those of ordinary skill in the art, and are not described in detail. In addition, the above definitions of each element and method are not limited to the various specific structures, shapes or methods mentioned in the embodiments, and those of ordinary skill in the art can easily modify or replace them, for example:

(1) Inductively coupled plasma (ICP) can also be replaced by reactive ion etching (RIE);

(2) SiO ₂ insulating layer can be used as SiN _x replacement;

Based on the above description, those skilled in the art should have a clear understanding of the disclosed mid-infrared superlattice interband transition laser and its preparation method.

To sum up, the present disclosure provides a mid-infrared superlattice interband transition laser and its preparation method, adopting a superlattice interband transition method, which can effectively increase the active The number of particles in the region is reversed to increase the gain of the laser, and the lasing wavelength of the device can also be adjusted by adjusting the width of the well in the superlattice. In addition, due to the use of a mechanism similar to the transition between bands, it can effectively suppress the laser at long wavelengths. The generation of intermittent recombination enables the device to work in a larger wavelength range, so the laser can cover the entire mid-infrared 2-5um band, and realize the work in the mid-infrared band. Using this structure can greatly improve the gain of the active region and Laser performance.

It should also be noted that the directional terms mentioned in the embodiments, such as "up", "down", "front", "back", "left", "right", etc., are only referring to the directions of the drawings, not Used to limit the protection scope of this disclosure. Throughout the drawings, the same elements are indicated by the same or similar reference numerals. Conventional structures or constructions are omitted when they may obscure the understanding of the present disclosure.

And the shape and size of each component in the figure do not reflect the actual size and proportion, but only illustrate the content of the embodiment of the present disclosure. Furthermore, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Unless known to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that can vary depending upon the desired properties obtained from the teachings of the present disclosure. Specifically, all numbers used in the specification and claims to represent the content of components, reaction conditions, etc., should be understood to be modified by the term "about" in all cases. In general, the expressed meaning is meant to include a variation of ±10% in some embodiments, a variation of ±5% in some embodiments, a variation of ±1% in some embodiments, a variation of ±1% in some embodiments, and a variation of ±1% in some embodiments ±0.5% variation in the example.

Furthermore, the word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

Words such as "first", "second", "third" and the like used in the description and claims to modify the corresponding elements do not in themselves imply that the elements have any ordinal numbers, nor The use of these ordinal numbers to represent the order of an element with another element or the order of the manufacturing method is only used to clearly distinguish an element with a certain designation from another element with the same designation.

In addition, unless specifically described or steps that must occur sequentially, the order of the above steps is not limited to that listed above and may be changed or rearranged according to the desired design. Moreover, the above-mentioned embodiments can be mixed and matched with each other or used with other embodiments based on design and reliability considerations, that is, technical features in different embodiments can be freely combined to form more embodiments.

Those skilled in the art can understand that the modules in the device in the embodiment can be adaptively changed and arranged in one or more devices different from the embodiment. Modules or units or components in the embodiments may be combined into one module or unit or component, and furthermore may be divided into a plurality of sub-modules or sub-units or sub-assemblies. All features disclosed in this specification (including accompanying claims, abstract and drawings) and any method or method so disclosed may be used in any combination, except that at least some of such features and/or processes or units are mutually exclusive. All processes or units of equipment are combined. Each feature disclosed in this specification (including accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Moreover, in a unit claim enumerating several means, several of these means may be embodied by the same item of hardware.

Similarly, it should be appreciated that in the above description of exemplary embodiments of the disclosure, in order to streamline the disclosure and to facilitate an understanding of one or more of the various disclosed aspects, various features of the disclosure are sometimes grouped together into a single embodiment, figure, or its description. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, disclosed aspects lie in less than all features of a single foregoing disclosed embodiment. Thus the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this disclosure.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present disclosure in detail. It should be understood that the above descriptions are only specific embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims (10)

1. infrared superlattices band-to-band transition laser in one kind, comprising:

Substrate (100) is N-type gallium antimony material；

Lower limit layer (200) is prepared on substrate (100), is the AlGaAsSb of n-type doping；

Lower waveguide layer (300) is prepared on lower limit layer (200), is undoped AlGaInAsSb；

Active area (400) is prepared on lower waveguide layer (300), is superlattices band-to-band transition active area, comprising:

Transport the InAs/AlSb superlattices (410) of electronics；And

Transport the InGaSb/AlSb superlattices (420) in hole；

Upper ducting layer (500), is prepared on active area (400), is undoped AlGaInAsSb；

Upper limiting layer (600) is prepared on ducting layer (500), the AlGaAsSb of p-type doping；And

Upper contact layer (700), is prepared on upper limiting layer (600), for the GaSb of p-type doping.

2. infrared superlattices band-to-band transition laser according to claim 1, wherein the InAs/ for transporting electronics AlSb superlattices (410) period 3-9 period, the gradual change in superlattices of the thickness of InAs, thickness in 1-3.5nm, AlSb's With a thickness of 1-2nm.

3. infrared superlattices band-to-band transition laser according to claim 1, wherein the hole that transports InGaSb/AlSb superlattices (420), wherein the gradient thickness of InGaSb and AlSb, period are 1-4 period, wherein In group is divided between 0.25-0.4 in InGaSb hole trap, the InGaSb hole trap with a thickness of 1-4nm, AlSb with a thickness of 1-2nm。

4. infrared superlattices band-to-band transition laser according to claim 1, wherein the lower limit layer (200) is N The aluminum gallium arsenide antimony material of type doping, component ratio Al_0.6-0.9GaAs_0.02-0.04Sb, tellurium doping concentration are 1e¹⁷-1e¹⁸cm^-3, With a thickness of 1.0 μm -2 μm.

5. infrared superlattices band-to-band transition laser according to claim 1, wherein the lower waveguide layer (300) is Undoped Al-Ga-In-As antimony material, component ratio Al_0.1-0.3GaIn_0.2-0.4As_0.15-0.35Sb, with a thickness of 300nm-600nm.

6. infrared superlattices band-to-band transition laser according to claim 1, wherein the upper ducting layer (500) is P The Al-Ga-In-As antimony material of type doping, component ratio Al_0.1-0.3GaIn_0.2-0.4As_0.15-0.35Sb, with a thickness of 300nm- 600nm。

7. infrared superlattices band-to-band transition laser according to claim 1, wherein the upper limiting layer (600) is P The aluminum gallium arsenide antimony material of type doping, component ratio Al_0.3-0.9GaAs_0.02-0.04Sb, beryllium doping concentration are 1e¹⁸-1e¹⁹cm^-3, With a thickness of 1.0 μm -2 μm.

8. infrared superlattices band-to-band transition laser according to claim 1, wherein the upper contact layer (700) is P The gallium antimony material of type doping, beryllium doping concentration are 1e¹⁹-8e¹⁹cm^-3, with a thickness of 250nm-500nm.

9. a kind of preparation method, be used to prepare claim 1 to 8 it is described in any item in infrared superlattices band-to-band transition laser Device, comprising:

Step A: epitaxial wafer used in infrared superlattices band-to-band transition laser in preparation；

Step B: the ridge waveguide of laser is prepared on the prepared epitaxial wafer of step A；

Step C: the epitaxial wafer surface deposition insulating layer of ridge waveguide has been prepared in step B；

Step D: on the basis of step C, the etching insulating layer above corresponding vallum prepares electrode window through ray；

Step E, p-type front electrode is prepared above the electrode window through ray prepared by step D；

Step F, N-shaped rear electrode is prepared at the back side of substrate；

Step G, piece is dissociated into a bar item, and the plated film on bar dissociation face of item；And

Step H, tube core is dissociated, flip chip bonding is on heat sink, thus infrared superlattices band-to-band transition laser in being made.

10. preparation method according to claim 9, wherein the material of insulating layer described in step C includes: SiO₂Or Si₃N₄。