CN1384990A - Long wavelength pseudomorphic InGa NPAsSb type-1 and type-11 active layers for GAAS material system - Google Patents

Abstract

The invention discloses improved structures of and techniques for forming light-processing (e.g., light-emitting and light-absorbing/sensing) devices, in particular Vertical Cavity Surface Emitting Lasers (VCSELs), such as may find use in telecommunications applications. The disclosed VSCAL devices and production methods provide for an active region having a quantum well structure grown on GaAs-containing substrates, thus providing processing compatibility for light having wavelength in the range 1.0 to 1.6 mu m. The active region structure combines strain-compensating barriers with different band alignments in the quantum wells to achieve a long emission wavelength while at the same time decreasing the strain in the structure. The improved functioning of the devices disclosed results from building them with multicomponent alloy layers having a large number of constituents. Each alloy layer may be selected in accordance with disclosed preferences so that the disparate constituents contribute both to the accumulated strain and to a longer emission/absorption wavelength. Additional strain-minimization barrier layers aid in compensating or ameliorating further the aggregate strain of the structure, thereby lowering to an optimum level the incidence of dislocation and other defects that detract from device performance and device lifetime. The invention discloses as a key constituent in the proposed alloy layers for the active region a substance, such as nitrogen (N), suitable for reducing bandgap energy (i.e., increasing light wavelength) associated with the layers, while at the same time lowering the lattice constant associated with the structure and hence lowering strain.

Description

Long-Wavelength Pseudomorphic InGaNAsSb Type I and Type II Active Layers for GAAS Material Systems

Vertical-cavity surface-emitting lasers (VCSELs) operating at 1.3 μm and 1.5 μm are expected to be used in low-cost optical telecommunications systems and data links. The implementation of these devices enabled digital communication applications, such as "fiber-to-the-home", over distances of only a few kilometers. While lasers operating at 1.3 μm wavelengths are of interest for high-speed communications because these lasers operate with minimal dispersion in optical fibers, 1.55 μm lasers are also of interest for long-distance communications because they emit with minimal absorption. In addition, long-wavelength lasers have a low operating voltage, making them attractive for integration with integrated Si-based circuits, and the development direction is towards lower and lower operating voltages with higher integration densities. Due to the potentially huge market for 1.3 and 1.5 μm VCSELs, a lot of research has been done, namely, developing devices mainly based on two substrates InP and GaAs by using different approaches. Although InP is the traditional substrate material for edge-emitting lasers, GaAs offers the advantages of lower substrate cost and potentially higher device performance.

In general, a VCSEL is a light emitting semiconductor device comprising two distributed Bragg reflectors (DBR) with an active region between them having a material capable of emitting light at a desired wavelength. Figure 1 schematically shows a typical VCSEL structure. In this case the active region comprises several InGaAs quantum wells separated by GaAs barriers and illustrates the general conduction band edge line required in one active region. The semiconductor structure is designed to have a minimum gap between electrons and holes in the active region where the two types of carriers recombine and emit light. The wavelength of emitted light is determined by the energy difference between electrons and holes in the active region. The particular active region shown is designed to emit light at 980nm, but emission at longer wavelengths requires the same design procedure. The _{AlxGa1 -xAs} plate is used to define the resonant cavity length which is a multiple of half the wavelength of the emitted laser wavelength λ. Its composition is shown together with the relative refractive index and bandgaps of the different layers. Since, in a VCSEL, the active region is short, typically much smaller than the laser wavelength (λ), photons experience only a small one-pass optical gain through the active region. Therefore, in order to achieve the purpose of exciting laser light, highly reflective structures are required on both sides of the active region. This can be easily achieved by using the same epitaxial growth process as required for the fabrication of the active area, or by dielectric deposition techniques. The mirror consists of λ/4 alternating layers of materials with different refractive indices. At the wavelength of excitation, part of the wave is reflected at the interface between these layers to constitute interference, resulting in a very high reflectivity in a narrow spectral region. The thin film is stacked on both sides of the active region, forming so-called distributed Bragg reflectors (DBRs), which typically have a reflectivity of 99 percent or higher.

A waveguide structure is required for the optical mode, such as the configuration shown in FIG. 2 . In an indexing waveguide device as shown in Figure 2, the optical mode is defined by etching away material around a pillar to form an air-post device. The current is then also confined within this cylindrical region. Alternatively gain waveguides may be used. High-resistivity regions can be created by exciting high-energy protons or ions in the device. This defines a region where the passing current is concentrated on the active region. The gain region is laterally confined and forms modes in the free region. Combinations of these schemes can also be used. Oxidation-limited devices have recently been vigorously developed. Optional oxidation of the mirror layer to form _{an AlxOy} cladding provides current confinement and waveguiding, which enables the device to have a low threshold current.

The working principle of the light-emitting structure can be reversible. If light of the appropriate wavelength is shone directly on such a device, a current is generated across its terminals, allowing it to function as a detector. For high-performance detectors, different optimizations are required to have different optimal structures than the emitters. Figure 3 shows a typical structure. However, the active region for light emission and detection uses the same layered structure as the conventional type.

VCSELs require active materials for high-quality lasing and mirrors with high reflectivity DBR. Common problems encountered in the production of existing VCSELs have been extensively reviewed by US Patent Nos. 5,719,894 and 5,719,895, which patents are hereby incorporated in their entirety. Generally, the production of VCSELs emitting in the 1.3 to 1.55 μm region is troubled by the following problems:

(1) It is difficult to produce efficient DBRs for InP substrates and has been found in practice to be

very ineffective;

(2) VCSEL grown with InP/InGaAsP due to the high thermal sensitivity and refraction of the material

The low rate nature makes it low performance;

(3) Growth on GaAs produces active materials for high-quality lasers for existing technologies

The VCSEL has proven to be unsuccessful.

Materials used for lattice matched mirrors on InP substrates are InP and InGaAsP. These materials also have drawbacks, namely:

(i) low refractive index grades; and

(ii) Poor thermosensitive properties.

The low index grades manifest themselves in the number of layers needed to produce a DBR mirror with the desired reflectivity. When comparing AlGaAs stacks grown on GaAs, stacks grown on InP require multiple InP/InGaAsP layers to produce the same reflectivity. In addition, InGaAsP exhibits higher thermal sensitivity than GaAs or AlAs. This adds to the thermal sensitivity of the device, eg heat in the active area, making it more difficult to achieve reliable continuous wave (CW) operation at room temperature. This problem is further exacerbated if operating currents are applied to these areas, since most materials require mirrors, which increase the distance over which heat conduction occurs and simultaneously increases the heat value generated.

Although GaAs offers significant advantages in terms of low substrate cost, single crystal growth techniques, and high reflectivity mirrors, growing active materials of high optical quality on GaAs is a problem that many researchers have attempted in a variety of way to solve this problem. A common way to solve this problem is through the use of gain biasing. For example, US Patent Nos. 5,719,894 and 5,719,895 to Jewell et al., which are incorporated herein by reference. Although the approach outlined by Jewell et al. appears to have some attractive effects, it has generally been found difficult to achieve emission of light at the desired wavelength with this approach because process parameters such as critical thickness have not been fully exploited. Specifically for U.S. Patent No. 5,719, No. 894 will encounter the following problems:

1. As taught by Jewell et al., adding nitrogen (N) to semiconductor materials, such as InGaAs to form InGaNAs or GaInNAs called "Guinness", has been proven to increase the wavelength. However, the amount of N required to achieve 1.3 or even 1.55 μm can often result in high defect levels that adversely affect device performance and device lifetime. These problems greatly increase with the amount of N added.

2. Although some researchers believe in the formation of tetravalent alloys, another view still holds that N is doped as an impurity or defect state, which will lead to saturation of the gain.

3. The addition of N is a complex technology. The problem is to reliably incorporate more than 1% N in the active material. Typically, the material is thus grown at low temperatures, resulting in poor crystalline quality and subsequent heat treatment. But these steps cannot completely resolve the defects brought about by low temperature growth.

Additionally, for US 5,719,895, the following problems/deficiencies may be encountered when applying this technology to semiconductors:

1. The growth of InAs/GaAs superlattice is extremely difficult under current technology because of the large lattice mismatch between InAs and GaAs.

2. In high-strain epitaxial growth, the layered structure cannot grow smoothly, even the well is below the critical thickness. The layered structure may exhibit surface roughness or corrugation, and may also appear island-like, with the amount of active area decreasing dramatically, leading to the construction of quantum dots for the purposes of the present invention which are considered to be comparable to "quantum islands". ) are functionally interchangeable.

3. Theoretical models used to describe strain usually describe the growth process too simply. Other growth methods, eg (Stranski-Krastanov), will result in quantum dot structures for thick wells below the critical thickness. In this case the amount of active area at which islands or spots are formed becomes very small. This will reduce the maximum achievable gain provided by the layered structure. Also, it is likely that the spot size is integral, which results in wider spectral lines, and lower material gain peaks.

4. Very smooth layered structures capable of reaching a critical thickness, as far as known, the structures proposed in connection with the present invention have never been experimentally realized. Even in this case where the supercrystalline structure consists of repeating units of a single InAs layer and a GaAs layer, strain buildup can lead to surface roughness before a critical thickness is reached. Inhomogeneities in the structure, such as ripples, will cause broad spectral lines and lower gain.

5. The growth of these structures is also likely to lead to the generation of material defects (such as dislocations). This will severely degrade the gain characteristics of the material and shorten the lifetime of any lasers produced from this material.

One of the most promising, albeit complex, approaches to avoid the prior art VCSEL problems outlined above is thin film synthesis where the active region and DBR are grown on separate InP substrates which are then bonded together , to form the VCSEL. This often results in complex manufacturing processes with yield issues and high costs for each device.

To ensure reliability and reproducibility and to overcome the limitations of the InP/InGaAsP material system, especially since GaAs-based technologies are generally more mature than InP-based technologies, the development of other GaAs-based structures is attracting considerable attention. However, materials that can be grown on GaAs and have a band gap suitable for emitting light at 1.3 μm have not been easily found.

In one approach, quantum dot (QD) structures have been developed. InGaAs QDs have been shown to be photoluminescent (PL) at 1.3 μm, and photodiode resonator operation at 1.27 μm has been achieved. Recently, edge-emitting QD lasers operating near 1.3 μm have also been demonstrated. Photoluminescence (PL) at room temperature (RT) at 1.3 μm with strained GaAsSb quantum wells (QWs) has been noted and lasing at 1.27 μm has been reported in edge emitting devices. In addition, a single GaInNAs QW is used in a GaAs-based VCSEL structure to emit light with a longer wavelength of 1.18 μm, and it works intermittently at RT. It is also noted that the PL wavelength reaches 1.33 μm in the GaAsSb/InGaAs dual QW sample with type II band edge. The feasibility and fabrication of edge-emitting LEDs with a type II bandedge structure for long-wavelength devices has been demonstrated.

Summary of the invention

The present invention overcomes the problems encountered in existing VCSEL devices, and provides a production method for emitting 1.0 to 1.6 μm wavelength by setting an active region with a quantum well structure. This quantum well can be used in lasers grown on GaAs substrates. This active region combines strain-compensating barriers with different energy band edges in the quantum wells to achieve long-wavelength emission while minimizing strain in the structure. The present invention provides a structure formed by the fabrication of multi-component alloy layers having many configurations. The alloy is formulated such that each component contributes to the cumulative strain and emission/absorption of long wavelength light. Devices made according to the present invention can be used for the emission and absorption of light, or the modulation of light, or either, and are particularly suited for successful or optimal emission and/or absorption of light having specific wavelengths based on their physical and optical properties . In this regard, it may be beneficial to provide and describe a device by reference to a wavelength at which it is capable of effectively operating, ie, absorbing and/or emitting light. The alloy composition used for the quantum well layer is optimized to achieve the longest wavelength possible, and the smallest total strain. In addition, the strain compensating barrier layer helps to further reduce the overall strain of the structure, thus having minimal dislocation configuration or other defects that adversely affect device performance and device lifetime. The most important constituent in the alloy-forming layers described here is nitrogen (N), which reduces the bandgap energy (longer wavelength) while simultaneously reducing the lattice constant and thus strain. Phosphorus (P) also has this property, and antimony (Sb) and indium (In) increase the lattice constant of a layered structure grown on GaAs and thus cause compressive strain. Adding N in amounts higher than a few percent is complicated and potentially leads to deterioration of crystal quality. Thus, in combination with other alloying components, N is used in an amount that is manageable from a technical point of view, while providing an important additional amount to maximize wavelength attainment.

The active layer structure described in the present invention is a synthesis of basic standard components as described below, all relying on quantum confinement. For quantum confinement, layered structures need to incorporate mutually different valence and conduction band energies from layer to layer. The simplest such quantum well structure is shown in FIG. 4 . A layer with a lower conduction band edge and a higher valence band edge—holes have an inverse energy scale—the layer is sandwiched between the higher conduction band edge and the lower valence band edge. Charge carriers, electrons in the conduction band and holes in the valence band, become trapped in the energy levels quantized by the structure and recombine very efficiently, with emission wavelengths between the lowest conduction band energy level and the highest valence band energy level consistent distance between lights. The device works as a detector, and such quantum wells have high absorption and good detection sensitivity. As previously stated, devices having such structures may have light processing utility, ie, act as light emitters or light receivers/detectors, or light modulators, or any or all of these as desired from time to time.

In order to improve the efficiency of quantum wells including this structure, as shown in FIG. 5 , several quantum wells are stacked in periodic order. When the quantum wells are tightly coupled, such an arrangement is called a supercrystalline lattice and has its own band structure along the periodic direction, forming artificial layered materials with unique properties. When the quantum wells are weakly coupled, the energy levels of the quantum wells are preserved so that the multiple quantum well band structures are simple multiples of the individual quantum wells.

In order to reduce the transition energy, as shown in Figure 6, two quantum well layers at different positions of the valence band edge and the conduction band edge can be directly combined. Thus type II quantum wells have a spatially separated region for trapping electrons and holes, enabling transitions between the lowest energy level in the deepest electron well and the highest energy level in the highest hole well. The advantage of low transition energy is usually accompanied by reduced transition efficiency, since the wave functions for electrons and holes are spatially separated and their overlap is reduced. The exact value of this overlap depends largely on the specific band structure, and the demonstrated configurations show very high efficiencies like the above (Type I) special direct quantum wells.

As shown in Fig. 7, an improved method of wave function overlap is to make the type II coupled well symmetrical, where a triple layer structure is formed to relatively lower the potential barrier between the two electron (hole) wells. In this case, the wave function of electrons (holes) has a high value on the axis of symmetry of the structure, where the wave function of holes (electrons) is a maximum. This results in high efficiency transitions and good device performance.

Typically, the quantum wells of the structures discussed here have a larger lattice constant than the substrate. To reduce the total accumulated strain in this structure, which can lead to defects that are detrimental to device performance, the barrier layers on both sides of the quantum well can be made of a material with a lower lattice constant value than the substrate. Although the layered structures are strained to each other, the average strain of the whole structure is reduced or even becomes zero. This design principle is called strain balance and is shown in Figure 8.

In order to overcome the problems encountered with prior art VCSEL devices and fabrication methods, the present invention discloses the use of strain compensating structures having Type I and Type II band edge lines. The use of strain compensation enables the growth of multiple layers without material quality degradation, thus providing a high degree of freedom in device design.

Brief description of attached drawings

Figure 1 is a schematic diagram of a general VCSEL structure showing conduction band energy/refractive index/material composition variation on the right. (current technology.)

Figure 2 shows a typical VCSEL structure showing (a) guiding waveguide device (b) gain waveguide device, (c) oxidation confining device. (current technology.)

Figure 3 shows the structure of a common detector using the same active region material as a VCSEL. (current technology.)

Figure 4 shows a type I quantum well.

Figure 5 shows a type I multiple quantum well.

Figure 6 shows a type II quantum well.

Figure 7 shows a type II symmetric quantum well.

Figure 8 shows the principle of strain compensation.

FIG. 9 shows a schematic diagram of the energy band edge line of the designed Type I strain-compensated QW system for emitting light near 1.3 μm.

Figure 10 compares bandgap energy points against strain for GaPAsSb continuum on GaAs. Negative strain values indicate compressive strain. The right-hand shaded area is a direct bandgap material, while the left-hand shaded area is an indirect bandgap material.

Fig. 11 is an A/B/C/B/A type I single quantum well utilizing material system 1 according to the present invention.

Fig. 12 is a type A/B/C/B/A I multiple quantum well utilizing material system 1 according to the present invention.

Fig. 13 is a type A/B/C/D/B/A type II single quantum well utilizing material system 2 according to the present invention.

Figure 14 is a type A/B/C/D/B/A II multiple quantum well utilizing material system 2 according to the present invention.

Figure 15 is an A/B/D/C/B/A Type II single quantum well utilizing material system 3 according to the present invention.

Figure 16 is an A/B/D/C/B/A Type II multiple quantum well utilizing material system 3 according to the present invention.

Figure 17 is an A/B/D/C/D/B/A Type II single quantum well utilizing material system 4 according to the present invention.

Figure 18 is a type A/B/D/C/D/B/A II multiple quantum well utilizing material system 4 according to the present invention.

Figure 19 is an A/B/C/D/C/B/A Type II single quantum well utilizing material system 5 according to the present invention.

Figure 20 is an A/B/C/D/C/B/A Type II multiple quantum well utilizing material system 5 according to the present invention.

Describe the preferred embodiment in detail

Although strained heterojunction _{InwGa1 - wNxPyAszSb1 -xyz} / _{AlpGa1 -pAs} /GaAs is used, the material system of the present _invention includes _: 1) compressively strained _{InwGa 1-w} N _x P _y As _z Sb _1-xyz quantum well and a tensile strained Al _q Ga _1-q N _r P _s As _1-rs barrier layer with type I band line; and 2) utilizing a II _{Compressively strained quantum wells and tensile strained Al q Ga 1- _ q} N _r P _s As _1-rs barrier layer. Both material systems were grown pseudomorphically on GaAs substrates. "Pseudomorphic" as used herein means having a sufficiently low density of misalignment dislocations for the fabrication of a laser with a sufficiently high lifetime. The present invention uses both type I and type II band edge lines.

The present invention can achieve emission or absorption by using a combination of single or multiple active materials grown on material A, with strain compensation material B, type I active material C, or with type II active materials C and D. Light in the 1.0μm to 1.6μm wavelength range.

For Type I active layers:

Material system 1=A-B-(C-B)[n times]-A, n=1, 2, 3...

For type II active layer:

Material system 2 = A-B-(C-D-B)[n times]-A, n=1, 2, 3...

Material system 3 = A-B-(D-C-B)[n times]-A, n=1, 2, 3...

Material system 4 = A-B-(D-C-D-B)[n times]-A, n=1, 2, 3...

Material system 5 = A-B-(C-D-C-B)[n times]-A, n=1, 2, 3...

The layers are:

A＝Al _p Ga _1-p As 0≤p≤1

B＝Al _q Ga _1-q N _r P _s As _1-rs 0≤q≤1; 0≤r≤0.1; 0≤s≤1

C=In _w Ga _1-w N _x P _y As _z Sb _1-xyz 0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1

D=In _a Ga _1-a N _b As _1-b 01≤a≤1; 0<b<0.1

The quantum wells - layers C and D - are compressively strained, while the spacer barriers are tensile strained - in the active region layer B is used to fully or partially compensate for the total strain. The degree to which the strain is compensated affects the overall thickness and number of quantum wells that can be grown dislocation-free. In the preferred embodiments of these multiple material systems, each layer of the layered structure is parallel to the other since one layer is built on top of the other.

Using the three-dimensional model theory, the schematic diagram of the energy band edge of the structure disclosed in the present invention can constitute a function of the material composition. As an illustrative example, Figure 9 shows the conduction and valence band edge lines for a particular material system made in accordance with the present invention. The composition of the barrier is GaP _0.42 As _0.58 and the composition of the well is GaP _0.37 As _0.08 Sb _0.55 . The room temperature bandgaps of these materials, shown together with discontinuous energy bands at the interface. The strain for the barrier is +1.5% (tensile) and 3% (compressive) for the well layer. For the barrier and well compositions given above, the transition energy between electrons and holes confined in the QW has been calculated to be 0.96 eV for an 8 nm wide barrier and well. This result is consistent with a wavelength near 1.3 μm, thus confirming the performance of the present invention working in the ideal wavelength range.

To demonstrate the feasibility of these structural experiments, cell growth test samples were cleaved by molecular beam epitaxy (MBE) with a valved chamber for precise control of layer composition by digital alloying. Through a combination of digital alloying and the use of intermixed Group V elements, it is practically possible to achieve layer stoichiometry to provide the desired wavelength characteristics (eg > 1.3 μm).

Surprisingly, in connection with the present invention it has been found that the doping of P and Sb enables VCSELs with wavelength > 1.3 μm while having a sufficiently longer lifetime than known conventional devices. This result is contrary to methods commonly used by those of ordinary skill in the art. In general, it is believed that the doping of P and Sb will result in a material with an indirect bandgap, especially when there is little or no In in the QW. Therefore, it is believed that this material has been largely or completely ignored as an element of telecommunications wavelength devices. Additionally, the effects of strain and the composition of the direct and indirect bandgap are not well defined. In connection with the present invention it has been found that the doping of P and N can reduce the strain of the material and thus the critical thickness becomes larger. This makes it easy to grow a high quality layer of pseudomorphic (defect free) material before the surface is roughened/rippled. The use of this material provides a new parametric space allowing the use of improved strain compensation layers to provide high quality epitaxial materials. By using the materials and methods disclosed in the present invention, the composition of the QW can also be selected so that the active material has a direct energy-to-band energy transition consistent with a wavelength around 1.3 μm.

The (In)GaNPAsSb material system, which readily emits light up to and beyond 1.3 wavelengths, is an arc-like parameter for large bandgap GaPSb. However, pseudomorphic GaPSb on GaAs is an indirect bandgap material with a compressive strain level below -5% and is therefore not suitable as an active material for lasers. In order to obtain a 0.96eV (1.3μm) direct bandgap material below the -5% strain level; a small amount of As or InAs must be added to GaPSb. For example, Figure 10 shows the bandgap energy of GaPAsSb versus strain. In Fig. 10, the ternary GaPAs, GaPSb, and GaAsSb ternary is close to the GaPAsSb quaternary region.

The region of the lowest energy band to the transition band for the label "direct bandgap" (in Figure 10) is between the Γ point of the conduction band and the Γ point of the valence band. These compositions are suitable as active materials for lasers. For the region labeled indirect bandgap, the lowest energy band transition band is an indirect transition between the X or L nadir of the conduction band and the Γ point of the valence band; these compositions are not suitable as active materials for lasers. The calculated bandgap energy values at the Γ point are shown in Figure 10.

The X, L and Γ band structure notations refer to individual electron or crystal momentum values. Directly transitioning energy levels is by electron motion between energy states with the same momentum (eg, Γ point to Γ point). Whereas, indirect transition levels rely on changes in momentum and energy levels during the transition. Indirect bandgap materials are not suitable as active materials for lasers, because the energy-to-band transition of light requires the adjustment of additional particles in order to save momentum; this can greatly reduce the probability of light transitions.

Since GaP has a large bandgap (>2eV) and an indirect bandgap, it is not obvious that the (In)Ga(N)PAsSb material system is suitable for GaAs-based long-wavelength lasers. The unremarkable properties of the (In)Ga(N)PAsSb material system make it suitable for GaAs-based lasers including, but not limited to:

1) Larger arc-shaped bandgap parameters of GaPSb; as shown in Figure 10, the bandgap of the middle element of the three elements of GaPSb is smaller than the bandgap of one of the endpoints of the two elements (GaP or GaSb).

2) A large range of mixed-group V components (P, As and Sb) here GaPAsSb are direct bandgap materials.

The addition of N and In to these alloys further reduces the bandgap energy and thus has a longer operating wavelength. N appears to be added as a localized state, causing a strong interaction between the narrow resonance band and the conduction band, thus reducing the original bandgap for direct transitions. It has been demonstrated that the addition of N in the active layer enables lasing in sharply dislocated VCSEL devices compared to N-free alloys with only a small N percentage. Because large amounts of N are difficult to incorporate, such as in InGaAs, achieving uniform emission 1.3 μm for device applications in these single-group-V (As) systems is a complex undertaking. Typically, the layered structure needs to be grown below the growth temperature and then annealed, resulting in high defect densities and structural distortions in the alloy, again apparently depending on the dislocation emission or absorption wavelength. The present invention avoids these difficulties by adding N in combination with the structure described above, enabling significant addition of dislocations in wavelength while maintaining strain and reducing defect density. Since Sb is a better match in terms of growth temperature and adhesion coefficient, especially for metal stable growth regimes, increasing the Sb fraction in these alloys instead of In with N allows for better N incorporation and thus better quality Layered structure.

An embodiment of the invention, represented here by system 1, comprises an active layer of a layered sequence which on a substrate may be A-B-C-B-A close to GaAs composition, i.e. comprising GaAs and/or its structure in substantial proportions and functional equivalents; where

A＝Al _p Ga _1-p As 0≤p≤1

B＝Al _q Ga _1-q N _r P _s As _1-rs 0≤q≤1; 0≤r≤0.1; 0≤s≤1

C=In _w Ga _1-w N _x P _y As _z Sb _1-xyz 0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1

For clarity of labeling and ease of understanding, the conceptual layered sequence is represented as A-B-C-B-A (described as an example only), which is characterized by a continuous stack of layers, each layer adjacent to the next layer represented (then followed by an example description only, A component The layer is adjacent to the B-component layer, which is adjacent to the C-component layer on the opposite side of the B-component layer, which in turn is adjacent to the B-component layer on the opposite side of the C-component layer, which is finally adjacent to the A-component layer on its opposite side. adjacent). The band structure of this schematic layered sequence is shown in FIG. 11 . In layer B r=s=0, the strain compensation can also be zero.

In another embodiment of the present invention, the C-B unit of the active layer can be repeated, such as the structure shown in FIG. 12 . In layer B r=s=0, the strain compensation can also be zero.

An embodiment of the invention, represented here by system 2, comprises an active layer of layered sequence A-B-C-D-B-A on a substrate close to the GaAs composition; wherein

A＝Al _p Ga _1-p As 0≤p≤1

B＝Al _q Ga _1-q N _r P _s As _1-rs 0≤q≤1; 0≤r≤0.1; 0≤s≤1

C=In _w Ga _1-w N _x P _y As _z Sb _1-xyz 0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1

D=In _a Ga _1-a N _b As _1-b 0≤a≤1; 0<b<0.1

The schematic band structure of this layered sequence is shown in FIG. 13 . In layer B r=s=0, the strain compensation can also be zero.

In another embodiment of the present invention, the C-D-B unit of the active layer can be repeated, as shown in the structure shown in FIG. 14 . In layer B r=s=0, the strain compensation can also be zero.

An embodiment of the invention, represented here by system 3, comprises an active layer of layered sequence A-B-D-C-B-A on a substrate close to the GaAs composition; wherein

A＝Al _p Ga _1-p As 0≤p≤1

B＝Al _q Ga _1-q N _r P _s As _1-rs 0≤q≤1; 0≤r≤0.1; 0≤s≤1

C=In _w Ga _1-w N _x P _y As _z Sb _1-xyz 0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1

D=In _a Ga _1-a N _b As _1-b 0≤a≤1; 0<b<0.1

The schematic band structure of this layered sequence is shown in FIG. 15 . In layer B r=s=0, the strain compensation can also be zero.

In another embodiment of the present invention, the D-C-B unit of the active layer can be repeated, such as the structure shown in FIG. 16 . In layer B r=s=0, the strain compensation can also be zero.

An embodiment of the invention, represented here by system 4, comprises an active layer of layered sequence A-B-D-C-D-B-A on a substrate close to the GaAs composition; wherein

A＝Al _p Ga _1-p As 0≤p≤1

B＝Al _q Ga _1-q N _r P _s As _1-rs 0≤q≤1; 0≤r≤0.1; 0≤s≤1

C=In _w Ga _1-w N _x P _y As _z Sb _1-xyz 0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1

D=In _a Ga _1-a N _b As _1-b 0≤a≤1; 0<b<0.1

The schematic band structure of this layered sequence is shown in FIG. 17 . In layer B r=s=0, the strain compensation can also be zero.

In another embodiment of the present invention, the D-C-D-B unit of the active layer can be repeated, as shown in the structure shown in FIG. 18 . In layer B r=s=0, the strain compensation can also be zero.

An embodiment of the invention, represented here by system 5, comprises an active layer of layered sequence A-B-C-D-C-B-A on a substrate close to the GaAs composition; wherein

A＝Al _p Ga _1-p As 0≤p≤1

B＝Al _q Ga _1-q N _r P _s As _1-rs 0≤q≤1; 0≤r≤0.1; 0≤s≤1

C=In _w Ga _1-w N _x P _y As _z Sb _1-xyz 0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1

D=In _a Ga _1-a N _b As _1-b 0≤a≤1; 0<b<0.1

The schematic band structure of this layered sequence is shown in FIG. 19 . In layer B r=s=0, the strain compensation can also be zero.

In another embodiment of the present invention, the D-C-D-B unit of the active layer can be repeated, such as the structure shown in FIG. 20 . In layer B r=s=0, the strain compensation can also be zero.

Apparently, for those of ordinary skill in the art, the methods and examples of the present invention described above, the uses and advantages of the present invention disclosed by them are only illustrative and exemplary, and cannot describe and limit the concept and scope of the present invention. The spirit and scope of the present invention are to be limited only by the following claims. All references mentioned above are incorporated herein in their entirety.

Claims (44)

1. A light processing device comprising: (a) a substrate and (b) an active region, wherein said substrate comprises a semiconductor material having a lattice constant, and wherein said active region comprises a plurality of layers , the layer comprising: (i) at least one pseudomorphic photoprocessing layer comprising In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1)and; at least one pseudomorphic barrier layer comprises Al _q Ga _1-q N _r P _s As _t Sb _1-rst (0≤q≤1; 0≤r≤0.1; 0≤s < 1, 0<t<1), and wherein each layer of said multilayer has a composition in said active region that is different from the composition of any adjacent layer. 2. The device of claim 1, wherein light processing includes processing selected from (a) emitting light; (b) receiving light; (c) sensing light; and (d) modulating light. 3. The device of claim 2, wherein said active region further comprises (iii) at least one pseudomorphic photomanipulation layer comprising In _a Ga _1-a N _b As _1-b (0≤a≤1; 0 <b<0.1). 4. A device as claimed in claim 3, wherein each layer of said multilayer structure in said active region is arranged substantially parallel in a common plane. 5. The device of claim 2, wherein said active region comprises a sequence of ABCBA layers, wherein layer _A comprises _{AlpGa1 -pAs} (0≤p≤1) and layer B comprises _{AlqGa1 -q} N _r P _s As _t Sb _1-rst (0≤q≤1; 0≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-syz (0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1), and wherein the band structure formed between the B layer and the C layer is A type I bandgap line. 6. The device defined by claim 2, wherein said active region comprises an AB-

A sequence of layers, where A layer includes Al _p Ga _1-p As (0≤p≤1), B layer includes Al _q Ga _1-q N _r P _s As _t Sb _1-rst (0≤q≤1; 0 ≤r≤0.1: 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1 ; 0 ≤ y ≤ 0.6; 0 < z < 1), and wherein the sequence of (CB) layers can be repeated n times adjacently and continuously, n being an integer multiple greater than 1, and between layers B and C The resulting band structure is a type I bandgap line. 7. The device of claim 2, wherein said active region comprises a sequence of ABCDBA layers, wherein _A layer comprises _{AlpGa1 -pAs} (0≤p≤1), and B layer comprises _{AlqGa1 -q} N _r P _s As _t Sb _1-rst (O≤q≤1; 0≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1;O≤y≤0.6;0<z<1), D layer includes In _a Ga _1-a N _b As _1-b ( 0≤a≤1; 0<b<0.1), and the band structure formed between the B and C layers is a type I bandgap line, and wherein the band structure formed between the B and D layers is A type I bandgap line, and where the band structure formed between the C and D layers is a type II bandgap line. 8. The device defined by claim 2, wherein said active region comprises an AB-

A sequence of layers, where A layer includes Al _P Ga _1-P As (0≤p≤1), B layer includes Al _q Ga _1-q N _r P _s As _t Sb _1-rst (0≤q≤1; 0 ≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1: 0<x<0.1 : 0≤y≤0.6; 0<z<1), the D layer includes In _a Ga _1-a N _b As _1-b (0≤a≤1; 0<b<0.1), and the (CDB) layer The sequence can be repeated n times adjacently and continuously, n is an integer multiple greater than 1, and the energy band structure formed between the B and C layers is a type I bandgap line, formed between the B and D layers The band structure of is a type I bandgap line, and the band structure formed between the C and D layers is a type II bandgap line. 9. The device of claim 2, wherein said active region comprises a sequence of ABDCBA layers, wherein _A layer comprises _{AlPGa1 -PAs} (0≤p≤1), and B layer comprises _{AlqGa1 -q} N _r P _s As _t Sb _1-rst (0≤q≤1; 0≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1; 0≤y≤0.6: 0<z<1), D layer includes In _a Ga _1-a N _b As _1-b ( 0≤a≤1; 0<b<0.1), and the band structure formed between the B and C layers is an I-type bandgap line, and the band structure formed between the B and D layers is an I A type II bandgap line, and the band structure formed between the C and D layers is a type II bandgap line. 10. The device defined by claim 2, wherein said active region comprises an AB- A sequence of layers, where A layer includes Al _P Ga _1-P As (0≤p≤1), B layer includes Al _q Ga _1-q N _r P _s As _t Sb _1-rst (0≤q≤1; 0 ≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1 ; 0≤y≤0.6; 0<z<), the D layer includes In _a Ga _1-a N _b As _1-b (0≤a≤1; 0<b<0.1), and the sequence of the (DCB) layer It can be repeated n times adjacently and continuously, n is an integer multiple greater than 1, the energy band structure formed between the B and C layers is a type I bandgap line, and the energy formed between the B and D layers The band structure is a type I bandgap line and the band structure formed between the C and D layers is a type II bandgap line. 11. The device of claim 2, wherein said _active region comprises a sequence of ABDCDBA layers, wherein layer A comprises _{AlPGa1 -PAs} (0≤p≤1), and layer B comprises _{AlqGa1 -q} N _r P _s As _t Sb _1-rst (0≤q≤1; 0≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1;0≤y≤0.6;0<z<1), D layer includes In _a Ga _1-a N _b As _1-b ( 0≤a≤1; 0<b<0.1), and wherein the band structure formed between the B and C layers is a type I bandgap line, and the band structure formed between the B and D layers is a A type I bandgap line, and the band structure formed between the C and D layers is a type II bandgap line. 12. The device defined by claim 2, wherein said active region comprises an AB- A sequence of layers, where A layer includes Al _P Ga _1-P As (0≤p≤1), B layer includes Al _q Ga _1-q N _r P _s As _t Sb _1-rst (0≤q≤1; 0 ≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1 ; 0≤y≤0.6; 0<z<1), the D layer includes In _a Ga _1-a N _b As _1-b (0≤a≤1; 0<b<0.1), and the (DCDB) layer The sequence can be repeated n times adjacently and continuously, where n is an integer multiple greater than 1, and wherein the band structure formed between the B and C layers is a type I bandgap line, between the B and D layers The formed band structure is a type I band gap line, and the band structure formed between the C and D layers is a type II band gap line. 13. The device defined by claim 2, wherein said active region comprises an AB-

A sequence of layers, where A layer includes Al _P Ga _1-P As (0≤p≤1), B layer includes Al _q Ga _1-q N _r P _s As _t Sb _1-rst (0≤q≤1; 0 ≤r≤0.1; 0≤s≤1, 0<t<1), and the C layer includes In _W Ga _1-w N _x P _y As _z Sb _1-xyz (0≤w≤1; 0<x<0.1 ; 0≤y≤0.6; 0<z<1), the D layer includes In _a Ga _1-a N _b As _1-b (0≤a≤1; 0<b<0.1), and the (CDCB) layer The sequence can be repeated n times adjacently and continuously, where n is an integer multiple greater than 1, and wherein the band structure formed between the B and C layers is a type I bandgap line, between the B and D layers The formed band structure is a type I band gap line and the band structure formed between the C and D layers is a type II band gap line. 14. A device as claimed in claim 2 or 3, wherein at least one of said plurality of layers comprising said active region is said to obtain a quantum dot matrix during growth, wherein at least one layer is formed. 15. The device of claim 2, wherein the wavelength of light processable by the device at a room temperature of about 300K is at least about 1150 nm. 16. The device of claim 2, wherein the wavelength of light processable by the device at room temperature above about 300K is at least about 1150 nm. 17. The device of claim 2, wherein the wavelength of light processable by the device at room temperature below about 300K is at least about 1150 nm. 18. The device defined by claim 2, wherein said substrate comprises GaAs having a lattice constant. 19. The device of claim 2, wherein said substrate comprises GaAs in combination with other additional substrate components selected from the group consisting of Al, In, and a dopant. 20. The device of claim 2, further comprising (c) a first conductive layer having a first conductivity type and being placed in electrical contact with the active region; (d) a second conductive layer having a second conductivity type layer juxtaposed in electrical contact with an active region; (e) electrically connected to said active region, wherein said electrical connection has the capability to handle electrical current, and wherein said treatment comprises a treatment selected from the group consisting of (i) supplying current to the active region; and (ii) receiving current from the active region. 21. The device of claim 20, wherein the bandgap of the first and second conductive layers is larger than the bandgap of the layered sequence in the active region. 22. The device of claim 20, further comprising a void semiconductor interface, wherein the semiconductor interface is suitable for photoprocessing. 23. The device of claim 22, wherein said semiconductor interface is formed by a process step selected from the group consisting of etching and bonding to form a substantially parallel plane perpendicular to each layer of said multilayer. cavity. 24. The device of claim 20, further comprising: (f) a grating layer disposed on said second conductive layer, wherein said grating layer comprises linearly extending over at least a portion of said active region, and wherein The grating layer defines an optical cavity having an optical resonance that coincides with a resonant energy along with a resonant wavelength, and wherein the resonant wavelength measured in microns in vacuum is approximately equal to 1.24, separated from the resonant energy measured in electron volts. 25. A device as claimed in claim 24, wherein the grating lines are shifted by n times a quarter of the resonant wavelength, where n is an integer greater than or equal to 1, thereby forming a phase shifted grating. 26. The device of claim 20, further comprising: (f) a lower reflector disposed below the active region; (g) and an upper reflector disposed above the active region, the The mirrors together with the resonant energy define an optical resonant cavity coincident with the resonant wavelength, and wherein the resonant wavelength measured in microns in vacuum is approximately equal to 1.24, separated from the resonant energy measured in electron volts. 27. A device as claimed in claim 26, wherein said lower reflector comprises a plurality of alternately adjacently disposed higher and lower refractive index layers. 28. The device of claim 27, wherein at least one of the plurality of lower index lower mirror layers comprises an oxide material. 29. A device as claimed in claim 26, wherein said upper mirror comprises a plurality of alternately adjacently disposed higher and lower refractive index layers. 30. The device of claim 29, wherein each said low index layer is selected from the group consisting of: an oxidic material; a low index dielectric material; and a low index semiconductor material. 31. The device defined by claim 29, wherein each said high index layer is selected from the group consisting of: a high index dielectric material; and a high index semiconductor material. 32. The device defined by claim 20, further comprising (f) a two-area aperture disposed between said upper mirror and said active region. 33. The device of claim 32, wherein a first region of the two-region aperture has a relatively low electrical resistance and a second region of the two-region aperture has a higher electrical resistance than the first region of the aperture . 34. The device of claim 32, wherein a first region of the two-region aperture has a higher refractive index than a second region of the two-region aperture. 35. The device of claim 32, wherein said two-region pore comprises an oxidizing material and wherein said second region of said pore is more oxidized than said first region of said pore. 36. The device of claim 32, wherein the two-area hole is formed by etching a columnar structure. 37. The device of claim 32, wherein the device comprises a photoelectric resonant cavity (RCPD). 38. The device of claim 32, wherein the device comprises a resonant cavity light emitting diode (RCLED). 39. The device of claim 32, wherein said device comprises a vertical cavity surface emitting laser (VCSEL). 40. The device of claim 32, wherein the device comprises a vertical cavity surface emitting laser for optical data communication. 41. The device of claim 40, wherein the emission wavelength of the device is between about 1260 nm and 1360 nm. 42. The device of claim 40, wherein the emission wavelength of the device is between about 1360 nm and 1460 nm. 43. The device of claim 40, wherein the emission wavelength of the device is between about 1460 nm and 1610 nm. 44. A device as claimed in claim 40, wherein said device comprises a light modulator.

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