A micro-cavity micro-led device integrated with a continuous metasurface

Abstract

This invention discloses a microcavity Micro-LED device with an integrated continuous metasurface, comprising, sequentially integrated along the Z-axis from bottom to top, a metal grating layer, a grating transition layer, a p-GaN layer, a quantum well active region layer, an n-GaN layer, an oxide DBR layer, and a continuous metasurface structure; the p-GaN layer, the quantum well active region layer, and the n-GaN layer constitute a micro-resonant cavity; the continuous metasurface structure is composed of several independent metasurface structures periodically distributed, and the XOY plane projection of each independent metasurface structure is an isosceles trapezoid. This invention not only solves the problems of poor spatial coherence, inconsistent emission direction, and difficulty in effective collection and utilization of linearly polarized light generated by polarized light Micro-LEDs in the prior art, but also solves the problems of difficult device fabrication, inability to achieve large-angle beam deflection, and large energy loss caused by integrated discrete metasurfaces.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor device technology, and particularly relates to a microcavity Micro-LED device with an integrated continuous metasurface. Background Technology

[0002] GaN-based Micro-LEDs have become a new generation of display technology, and Micro-LEDs with polarization emission capabilities are also finding increasing applications in many fields, such as near-eye displays and medical imaging.

[0003] To enable Micro-LEDs to emit linearly polarized light, early methods utilized biaxial stress in the epitaxy of non-polar m-plane LEDs, causing valence band splitting and thus generating linearly polarized light. However, this resulted in an excessively low extinction ratio (ER), unsuitable for practical applications. In reality, commonly used GaN LEDs are Micro-LEDs grown on c-plane sapphire substrates. They offer advantages such as high efficiency, high power, and long lifespan, but the light emitted by these Micro-LEDs lacks a fixed polarization direction.

[0004] In existing technologies, a common approach is to add a grating structure to the light-emitting surface of a Micro-LED. By adjusting parameters such as the grating's period, duty cycle, and thickness, the grating acts as a polarizer, filtering out linearly polarized light with a single polarization direction. However, the linearly polarized light generated by this method has poor spatial coherence and an unstable emission direction, making it difficult to collect and utilize the polarized light effectively.

[0005] Metasurfaces are ultrathin optical components composed of two-dimensional structures (such as nanopillars) at the wavelength or subwavelength level. They can alter the phase, amplitude, and polarization of light and can be used in various applications such as beam control, lens imaging, and 3D displays. Discrete subwavelength metasurfaces are commonly used for device integration. Devices integrating discrete metasurfaces are difficult to fabricate, have poor robustness, struggle to achieve large-angle beam deflection, and suffer from energy loss, exhibiting significant drawbacks.

[0006] In summary, the linearly polarized light generated by existing polarized Micro-LEDs exhibits poor spatial coherence and an unstable emission direction, making it difficult to effectively collect and utilize. To control the light wave, integrated metasurface structures are considered; however, conventional integrated discrete metasurface devices have many drawbacks, such as difficulty in fabrication, inability to deflect the beam at large angles, and high losses. Summary of the Invention

[0007] Technical problem solved: This invention discloses a microcavity Micro-LED device with an integrated continuous metasurface that emits linearly polarized light at a specified angle. It not only solves the problems of poor spatial coherence of linearly polarized light generated by existing polarized light Micro-LEDs, inconsistent emission direction, and difficulty in effective collection and utilization, but also solves the problems of difficult device fabrication, inability to achieve large-angle beam deflection, and large energy loss caused by integrated discrete metasurfaces.

[0008] Technical solution:

[0009] A microcavity micro-LED device integrating a continuous metasurface, the microcavity micro-LED device comprising, sequentially integrated along the Z-axis from bottom to top, a metal grating layer, a grating transition layer, a p-GaN layer, a quantum well active region layer, an n-GaN layer, an oxide DBR layer, and a continuous metasurface structure:

[0010] The metal grating layer includes several periodically arranged grating structures, and the grating transition layer includes several periodically arranged grating transition structures. The projections of the grating transition layer and the metal grating layer on the XOY plane completely overlap.

[0011] The n-GaN layer, the quantum well active region layer, and the p-GaN layer constitute a micro resonant cavity: the projection of the oxide DBR layer on the XOY plane coincides with the n-GaN layer, the quantum well active region MQW layer, and the p-GaN layer;

[0012] The continuous metasurface structure is composed of several independent metasurface structures periodically distributed, and the XOY plane projection of each independent metasurface structure is an isosceles trapezoid.

[0013] Furthermore, the metal grating layer is made of aluminum with a thickness of 180nm to 220nm; the width of a single grating structure ranges from 100nm to 110nm, and the grating period ranges from 160nm to 165nm.

[0014] Furthermore, the grating transition layer is made of MgF2 with a thickness ranging from 25nm to 35nm; the width and period of the grating dielectric structure are consistent with the width and period of the grating structure.

[0015] Furthermore, the cavity length of the micro-resonant cavity formed by the n-GaN layer, the quantum well active region layer, and the p-GaN layer is 400 nm.

[0016] Furthermore, the n-GaN layer, the quantum well active region layer, and the p-GaN layer are projected onto the XOY plane and overlap, forming a square or rectangle with a side length ranging from 1 μm to 10 μm.

[0017] Furthermore, the materials of the n-GaN layer and the p-GaN layer are GaN, and the thickness ranges from 100 to 200 nm; the real part of the refractive index of the material of the quantum well active region layer is 2.49; the electric dipole exists in the quantum well active region, and the emission center wavelength is 500 nm.

[0018] Furthermore, the oxide DBR layer is composed of 6 pairs of oxide layers stacked sequentially, each pair of oxide layers being composed of a TiO2 layer and a SiO2 layer, wherein the thickness of the SiO2 layer is 94 nm and the thickness of the TiO2 layer is 66 nm.

[0019] Furthermore, the continuous metasurface material structure uses GaP as its material, with a real part of refractive index of 3.58 at 500 nm; the periodic spacing between adjacent independent metasurface structures along the x-axis is 1 μm, and the periodic spacing along the y-axis is 140 nm; the projection of a single independent metasurface material structure onto the XOY plane is an isosceles trapezoid, with an upper side length ranging from 58 nm to 62 nm, a lower side length ranging from 108 nm to 112 nm, and a height of 830 nm; the thickness of a single independent metasurface material structure ranges from 270 to 275 nm.

[0020] Beneficial effects:

[0021] First, the integrated continuous metasurface microcavity Micro-LED device of the present invention integrates an upper oxide DBR layer and a lower MgF2-A1 double-layer grating layer to form a micro resonant cavity. Compared with traditional LEDs, the light emitted by the microcavity Micro-LED has better spatial coherence and collimation.

[0022] Secondly, the integrated continuous metasurface microcavity Micro-LED device of the present invention replaces the traditional bottom metal reflector with a MgF2-AL grating layer. By rationally designing the grating parameters, it can achieve the function of reflecting only specific polarization direction (TE polarized light) and transmitting TM polarized light within a specific wavelength range. It also has high reflectivity and extinction ratio. Through integration, it can realize the function of Micro-LED emitting linearly polarized light with a single polarization direction.

[0023] Third, the integrated continuous metasurface microcavity Micro-LED device of the present invention, compared with the traditional polarized light Micro-LED with integrated grating at the LED emission port, has better coherence of the emitted linearly polarized light by integrating a resonant cavity, which enables it to be better collected and utilized.

[0024] Fourth, the integrated continuous metasurface microcavity Micro-LED device of the present invention, by integrating a continuous metasurface structure above the micro-resonant cavity Micro-LED, consisting of several independent metasurface structures whose XOY planes are projected as isosceles trapezoids, can achieve angle control of linearly polarized light, enabling it to emit linearly polarized light at a specified angle. Compared with the discrete metasurfaces commonly used for Micro-LED integration, this design is easier to fabricate and can achieve large-angle deflection.

[0025] Fifth, the integrated continuous metasurface microcavity Micro-LED device of the present invention has the function of emitting polarized light at a specified angle, which solves the problems of poor light coherence and uncontrollable emission direction of traditional polarized light Micro-LEDs. The present invention has potential applications in fields such as near-eye display and medical bioimaging. Attached Figure Description

[0026] Figure 1 This is a three-dimensional schematic diagram of a microcavity Micro-LED device with an integrated continuous metasurface according to an embodiment of the present invention.

[0027] Figure 2 This is a cross-sectional view along the XOZ plane of the integrated continuous metasurface micro-cavity Micro-LED device according to an embodiment of the present invention.

[0028] Figure 3(a) is a top view of the continuous metasurface structure added to the upper layer of the DBR structure in step (5), and Figure 3(b) is a three-dimensional schematic diagram of a single structure of the continuous metasurface.

[0029] Figure 4 This is a graph showing the TE and TM polarized light reflectance curves of the MgF2-Al grating layer in this embodiment, as well as the relationship between the extinction ratio (ER) and wavelength.

[0030] Figure 5(a) , 5(b) These are schematic diagrams illustrating the structure and light emission of a conventional Micro-LED and a Micro-LED with an integrated micro-resonant cavity, respectively. Figure 5(c) , 5(d) This is a polar coordinate comparison diagram of the emission modes of ordinary Micro-LEDs and Micro-LEDs with integrated micro-resonant cavities.

[0031] Figure 6(a) is a far-field diagram of the beam deflection above the continuous metasurface obtained by simulation in this embodiment, and Figure 6(b) is a curve of transmittance and deflection efficiency of the beam above the continuous metasurface obtained by simulation in this embodiment.

[0032] Figure 7(a) is a polar coordinate diagram of the deflected TE polarized light emitted by a vertically structured micro-LED with an integrated continuous metasurface, and Figure 7(b) is a far-field diagram above the corresponding structure.

[0033] Figure 8(a) is a polar coordinate distribution diagram of the microcavity Micro-LED device of the present invention realizing TE polarized light emission at 50°, and Figure 8(b) is a far-field diagram above the corresponding structure. Detailed Implementation

[0034] The following embodiments are provided to enable those skilled in the art to more fully understand the present invention, but do not limit the invention in any way.

[0035] Example 1

[0036] This invention discloses a microcavity Micro-LED device with an integrated continuous metasurface. The microcavity Micro-LED device includes a metal grating layer, a grating transition layer, a p-GaN layer, a quantum well active region layer, an n-GaN layer, an oxide DBR layer, and a continuous metasurface structure, which are sequentially integrated from bottom to top along the Z-axis.

[0037] The metal grating layer includes several periodically arranged grating structures, and the grating transition layer includes several periodically arranged grating medium structures. The projections of the grating transition layer and the metal grating layer on the XOY plane completely overlap.

[0038] The n-GaN layer, the quantum well active region layer, and the p-GaN layer constitute a micro resonant cavity; the projection of the oxide DBR layer on the XOY plane coincides with the n-GaN layer, the quantum well active region MQW layer, and the p-GaN layer.

[0039] The continuous metasurface structure is composed of several independent metasurface structures periodically distributed, and the XOY plane projection of each independent metasurface structure is an isosceles trapezoid.

[0040] like Figure 1 As shown, the overall three-dimensional structure of the microcavity Micro-LED device in this embodiment, from bottom to top along the z-axis, consists of a metal grating layer 1, a grating transition layer 2, a p-GaN layer 3, a quantum well active region layer 4, an n-GaN layer 5, an oxide DBR layer 6, and a continuous metasurface structure 7. In this embodiment, the projections of the four layers—p-GaN layer 3, quantum well active region layer 4, n-GaN layer 5, and oxide DBR layer 6—along the z-axis onto the XOY plane form squares with sides of 3 μm, and they completely overlap. In the simulation, an electric dipole is placed in the MQW layer to simulate Micro-LED emission, and the emission center wavelength is set to 500 μm. Therefore, this embodiment's structure emits green light via a wavelength of 500 μm.

[0041] The projection of a single grating transition layer structure onto the XOY plane is rectangular, with a relatively short length along the x-axis and a length along the y-axis that is 3 μm, consistent with the side length of the n-GaN layer's projection onto the XOY plane along the y-axis. This structure is periodically distributed along the x-axis. At the XOY projection location, the grating transition layer 2 is entirely covered by the p-GaN layer.

[0042] In the three-dimensional structure, the metal grating layer 1 is below the grating transition layer 2, and the two are completely overlapped one-to-one at the projection of the XOY plane.

[0043] Figure 2 This is a cross-sectional view of the structure along the XOZ plane in this embodiment.

[0044] Preferably, the metal grating layer 1 is made of Al, with a thickness H1 of 200 nm, a single grating structure width W1 of 103.04 nm, and a grating period P1 of 161 nm.

[0045] Preferably, the metal dielectric layer 2 is made of MgF2 with a thickness H1 of 30 μm. The width and period of a single grating transition layer 2 are consistent with those of the metal grating layer 1, i.e., W1 is 103.04 nm and the grating period P1 is 161 nm.

[0046] Preferably, p-GaN, MQW, and n-GaN constitute the cavity of the resonant cavity. The total cavity thickness L is designed based on the resonance condition of the Fabry-Perot interferometer, i.e., L = m * λ / n (where m is a positive integer and n is the refractive index). According to the formula, the cavity length L = 400 m. Therefore, in this embodiment, H9 is set to 150 m, H10 to 100 m, and H11 to 150 m. The refractive index of MQW is set to 2.45 at a wavelength of 500 m.

[0047] Preferably, the oxide DBR layer 6 is composed of alternating SiO2 and TiO2 layers, and in this embodiment, it consists of a total of six TiO2-SiO2 layers. The thickness of each layer is selected according to the formula: n (refractive index) * H = λ / 4. Therefore, in this embodiment, the SiO2 thickness H12 is 94 nm and the TiO2 layer thickness H13 is 66 nm.

[0048] The continuous metasurface structure 7 consists of a series of repeating independent structures, each of which projects as an isosceles trapezoid in the XOY plane, with its height parallel to the x-axis. These independent structures are periodically arranged above the n-GaN layer, covering it, and the projection of this layer in the XOY plane is shown in Figure 3(a).

[0049] Preferably, the individual metasurface structure of the continuous metasurface structure 7 is shown in Figure 3(b). The continuous metasurface material is GaP, with a real refractive index of 3.58 at 500 nm. The imaginary refractive index can be considered as 0, so the material absorption characteristics are not considered. In this embodiment, the metasurface period Px is 1 μm, Py is 140 nm, the XOY plane cross-section of the individual metasurface structure is an isosceles trapezoid with an upper side length W3 of 60 nm, a lower side length W4 of 110 nm, a height Lx of 830 nm, and a structural thickness H3 of 273 nm.

[0050] Figure 1 In this embodiment, 1 and 2 constitute the bottom MgF2-Al double-layer grating layer, serving as the bottom reflector of the microresonator and also providing polarization filtering functionality. The simulation results obtained after parameter optimization of the bottom grating are as follows: Figure 4 As shown, at a representative emission wavelength of 500 nm, the extinction ratio (ER) of this Micro-LED reaches 54 dB, the reflectivity (RTE) of TE-polarized light is approximately 0.895, and the reflectivity (RTM) of TM-polarized light is approximately 3.2 e -6 Traditional GaN Micro-LEDs have an emission spectrum linewidth of 20 nm, and in the 490–510 nm band, the extinction ratio (ER) is generally greater than 20 dB, and the TE polarized light reflectivity is also relatively high.

[0051] In this embodiment, the bottom of the structure integrates a metal grating layer 1 and a grating transition layer 2 to form the bottom reflector of the resonant cavity, while the top oxide DBR layer 6 forms the top reflector, thus forming a micro-resonant cavity (Micro-LED). This improves the spatial coherence and collimation of the light emitted by the Micro-LED. Simultaneously, due to the effect of the polarization grating, the light emitted by the Micro-LED in this resonant cavity is almost entirely TE-polarized light.

[0052] Figure 5(a) shows the structure and luminous characteristics of a conventional Micro-LED. Due to its spontaneous emission characteristics, the conventional Micro-LED exhibits poor coherence and collimation, resulting in an approximately Lambertian light distribution. In the structure shown in Figure 5(a), a metal grating layer 1 and a grating transition layer 2 are integrated at the bottom to form a bottom reflector of the resonant cavity, and an oxide DBR layer 6 forms a top reflector, thus creating a micro-resonant cavity Micro-LED, as shown in Figure 5(b). The emitted light exhibits better spatial coherence and improved collimation, and can be approximated as planar light. Figure 5(c) is the polar coordinate diagram of the radiation mode of the structure in Figure 5(a). This diagram shows that both TE-polarized and TM-polarized light emission exhibit a Lambertian distribution, with poor spatial coherence and relatively dispersed light emission. Figure 5(d) is the polar coordinate diagram of the radiation mode of the structure in Figure 5(b). This diagram shows that the integration of the resonant cavity significantly improves the coherence and collimation of the emitted TE-polarized light, concentrating the light within a narrow angular range close to the surface normal. Since the relative magnitude of TM polarized light is almost zero, this micro-resonant cavity Micro-LED can be regarded as emitting only TE polarized light.

[0053] By adjusting the structural parameters using the generalized Snell's law, the continuous metasurface 7 in the embodiment was used to control the light deflection by 30°. The optimized structure, as shown in Figure 3(b), was simulated individually using Lumerical FDTD. Periodic boundary conditions were set for the x and y axes, and PML boundary conditions were set for the z axis. The incident plane light was TE-polarized light with a center wavelength of 500 nm. The far-field image monitored by the monitor above the structure is shown in Figure 6(a). The plane light underwent a 30° deflection, consistent with the expected design angle. Figure 6(b) shows the transmittance and deflection efficiency of this structure. At 500 nm, the transmittance is approximately 82%, and the deflection efficiency is approximately 79%, indicating good overall performance within this wavelength range.

[0054] The optimized continuous metasurface structure 7 was periodically arranged on the oxide DBR layer 6, i.e., a continuous metasurface structure layer was integrated on the structure shown in Figure 5(b). To verify whether the overall structure could achieve the expected function, the electric dipoles located in the MQW layer were set to emit TE-polarized light and TM-polarized light, respectively. The simulation results are shown in Figure 7. From the polar coordinate diagram of the emission mode 7(a), it can be seen that the TE-polarized light was deflected by 30° as expected, while the TM-polarized light could not be emitted at all due to the effect of the bottom polarization grating. At the same time, the continuous metasurface also had no effect on the TM-polarized light. Figure 7(b) is the far-field diagram of the light distribution vertically above the structure, which shows that the emitted light of the structure satisfies the 30° deflection.

[0055] Adjusting the parameters in Figure 3(b) according to the generalized Snell's law formula allows control over the deflection of light at other angles. When Px is 660 nm and Lx is 485 nm, the adjusted structure is periodically arranged on the upper side of the DBR, and the simulation results are shown in Figure 8. From the polar coordinate diagram of the emission mode in Figure 8(a), it can be seen that the TE polarized light is deflected by 50° as expected, a large-angle deflection. Figure 8(b) is the far-field diagram of the light distribution vertically above the structure, thus showing that the emitted light of this structure achieves a 50° deflection.

[0056] In summary, this invention provides a vertical microcavity Micro-LED structure with a specified angle of polarization emitted from an integrated continuous metasurface. In this invention, the MgF2-Al grating layer at the bottom achieves a reflectivity of 89.5% for TE-polarized light at 500 nm and an extinction ratio of 54 dB. Through the integration of the continuous metasurface, large-angle deflection of polarized light can be achieved; in this embodiment, deflections of 30° and 50° are realized. This invention not only solves the problems of poor coherence, inconsistent emission direction, and difficulty in effective collection and utilization of linearly polarized light generated by existing polarized Micro-LEDs, but also addresses the difficulties in fabricating devices, the inability to achieve large-angle beam deflection, and significant energy loss caused by integrating discrete metasurfaces.

[0057] Example 2

[0058] Based on the aforementioned structure, this invention also proposes a simulation method for a vertical microcavity Micro-LED structure with an integrated continuous metasurface and the function of emitting linearly polarized light at a specified angle. The simulation analysis is performed using Lumerical FDTD simulation software, and the simulation method includes the following steps:

[0059] (1) The initial Micro-LED structure is obtained by stacking p-GaN layer, quantum well active region MQW layer and n-GaN layer from bottom to top along the positive z-axis.

[0060] (2) An oxide DBR layer is superimposed on the n-GaN layer described in step (1) as an upper reflector.

[0061] (3) Add a grating transition layer below the p-GaN layer of the structure described in step (2).

[0062] (4) Add a metal grating layer below the grating transition layer of the structure described in step (3).

[0063] (5) A continuous metasurface structure arranged in a periodic pattern is superimposed on the oxide DBR layer of the structure described in step (4).

[0064] In step (1), the n-GaN layer, the quantum well active region MQW layer, and the p-GaN layer are all rectangular in structure in the simulation. Their projections onto the XOY plane coincide, forming squares or rectangles with side lengths ranging from 1 μm to 10 μm. The n-GaN and p-GaN layers are made of GaN. The MQW layer has a refractive index with a real part of 2.49. An electric dipole exists in the MQW layer, with an emission center wavelength of 500 nm.

[0065] In step (2), each oxide DBR layer is formed by stacking SiO2 and TiO2, and the DBR layer contains a total of six pairs of SiO2-TiO2 structures. The projection of the DBR layer onto the XOY plane coincides with the n-GaN layer, the quantum well active region MQW layer, and the p-GaN layer. The SiO2 layer thickness H12 is 94 nm, and the TiO2 layer thickness H13 is 66 nm. This oxide DBR layer serves as a reflector, forming the upper part of the resonant cavity.

[0066] In step (3), the grating transition layer material is MgF2, which completely covers the lower end of the n-GaN layer. The projection of a single structure onto the XOY plane has a length of 100–110 nm along the x-axis, and its length along the y-axis is consistent with the side length of the n-GaN layer's projection onto the XOY plane along the y-axis. This structure is periodically distributed along the x-axis, with a periodicity ranging from 160 to 165 nm, and the overall length of the structure along the x-axis is consistent with the length of the n-GaN along the x-axis. The thickness of the grating transition layer along the z-axis ranges from 25 to 35 nm.

[0067] In step (4), the metal grating layer material is Al, which completely covers the lower end of the grating transition layer. It is also periodically distributed along the x-axis, and the period, length along the x-axis and length along the y-axis in the XOY plane are completely consistent with the grating transition layer. From the projection on the XOY plane, the two completely overlap. The thickness of the structure along the z-axis ranges from 180 to 220 nm.

[0068] In step (5), the continuous metasurface material is GaP, which consists of periodically arranged structures. The projection of a single structure onto the XOY plane is an isosceles trapezoid. The upper side length of the isosceles trapezoidal structure along the two parallel sides of the y-axis is 58–62 nm, and the lower side length is 108–112 nm. The variation of the period along the x-axis between individual metasurface structures and the variation of the height of the isosceles trapezoid on the plane can jointly control the variation of the deflection angle of linearly polarized light. The period along the y-axis is fixed at 140 nm, and the height of the continuous metasurface structure along the z-axis is 270–275 nm.

[0069] The center wavelength of the emission band of the microcavity Micro-LED device obtained by simulation in this embodiment is 500nm, which is visible green light.

[0070] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A micro-cavity Micro-LED device of integrated continuous metasurface, characterized in that, The microcavity Micro-LED device includes, from bottom to top along the Z-axis, a metal grating layer, a grating transition layer, a p-GaN layer, a quantum well active region layer, an n-GaN layer, an oxide DBR layer, and a continuous metasurface structure. The metal grating layer includes several periodically arranged grating structures, and the grating transition layer includes several periodically arranged grating transition structures. The projections of the grating transition layer and the metal grating layer on the XOY plane completely overlap. The n-GaN layer, the quantum well active region layer, and the p-GaN layer constitute a micro resonant cavity; the projection of the oxide DBR layer on the XOY plane coincides with the n-GaN layer, the quantum well active region MQW layer, and the p-GaN layer. The continuous metasurface structure is composed of several independent metasurface structures periodically distributed, and the XOY plane projection of each independent metasurface structure is an isosceles trapezoid.

2. The microcavity Micro-LED device of claim 1, wherein, The metal grating layer is made of aluminum and has a thickness of 180nm to 220nm; the width of a single grating structure ranges from 100nm to 110nm, and the grating period ranges from 160nm to 165nm.

3. The microcavity Micro-LED device of claim 1, wherein, The grating transition layer is made of MgF2 with a thickness ranging from 25 nm to 35 nm; the width and period of a single structure in the grating transition layer are consistent with the width and period of the grating structure. 4.The micro-cavity Micro-LED device of claim 1, wherein, The cavity length of the microresonant cavity composed of the n-GaN layer, the quantum well active region layer, and the p-GaN layer is 400 nm. 5.The micro-cavity Micro-LED device of claim 1, wherein, The n-GaN layer, the quantum well active region layer, and the p-GaN layer are projected onto the XOY plane and form a square or rectangle with a side length ranging from 1 μm to 10 μm.

6. The micro-cavity Micro-LED device with integrated continuous metasurface according to claim 1, characterized in that, The n-GaN layer and p-GaN layer are made of GaN, and their thicknesses range from 100 to 200 nm. The active region of the quantum well is made of a material with a real part of refractive index of 2.

49. An electric dipole exists in the active region of the quantum well, with an emission center wavelength of 500 nm.

7. The integrated continuous metasurface microcavity Micro-LED device according to claim 1, characterized in that, The oxide DBR layer is composed of 6 pairs of oxide layers stacked sequentially. Each pair of oxide layers is composed of a TiO2 layer and a SiO2 layer stacked together, wherein the thickness of the SiO2 layer is 90-100 nm and the thickness of the TiO2 layer is 50-80 nm.

8. The micro-cavity Micro-LED device with integrated continuous metasurface according to claim 1, characterized in that, The continuous metasurface material structure uses GaP as its material, with a real part of refractive index of 3.58 at 500 nm. The periodic spacing between adjacent independent metasurface structures along the x-axis is 1 μm, and the periodic spacing along the y-axis is 140 nm. The projection of a single independent metasurface material structure onto the XOY plane is an isosceles trapezoid with an upper side length ranging from 58 nm to 62 nm, a lower side length ranging from 108 nm to 112 nm, and a height of 830 nm. The thickness of a single independent metasurface material structure ranges from 270 to 275 nm.

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