A continuous domain bound state laser based on a hybrid cavity structure and a preparation method thereof

Abstract

The application discloses a continuous domain bound state laser based on a mixed cavity structure and a preparation method thereof. The laser comprises, from bottom to top along a vertical direction, a substrate, an optical confinement layer, an N-type interval layer, an active layer, a P-type interval layer, a photonic crystal layer and a current expansion layer. The optical confinement layer at the bottom and the photonic crystal layer at the top jointly form a vertical mixed resonant cavity, and the active layer is located in the resonant cavity and maintains an un-etched complete layered structure. The photonic crystal layer is provided with a periodic nano-pore array penetrating through and is configured to support a BIC mode. The application separates the gain medium and the optical field regulation structure physically, avoids etching damage of the active layer in a traditional process, and significantly reduces surface non-radiation recombination loss. Meanwhile, in combination with the current expansion layer design, efficient vertical heat dissipation and uniform electric injection of the device are realized, and the device has the advantages of low threshold, high single-mode stability and wavelength regulation and the like.

Description

Technical Field

[0001] This invention relates to semiconductor optoelectronic device technology, specifically to a continuous domain bound state laser based on a hybrid cavity structure and its fabrication method. Background Technology

[0002] Continuous bound states (BICs) have attracted widespread attention in fields such as low-threshold lasers, nonlinear optics, and high-sensitivity sensing due to their theoretically infinite quality factor. However, transforming the physical mechanism of BICs from theory or optical pumping experiments into practical electrically injected lasers faces a huge technological gap, rather than a simple combination of structures: (1) Active region damage problem: Traditional etching processes that directly etch the active region introduce a large number of sidewall defects and nonradiative recombination centers, resulting in severe nonradiative losses and significantly reducing the luminous efficiency and gain characteristics of the device. (2) Heat dissipation difficulties: Traditional photonic crystal plate structures based on suspended or thin-film structures have low thermal conductivity, and embedded structures are not conducive to heat dissipation to the substrate, resulting in poor thermal stability of the device under high power operation. (3) Control difficulties: Laser characteristics (such as wavelength and threshold) are extremely sensitive to the geometric parameters of the photonic crystal plate, and once fabricated, it is difficult to independently control the optical field without affecting the gain medium through external means. (4) Electrical injection difficulties: The formation of BIC modes is highly dependent on the symmetry of the photonic crystal structure and the high degree of radiation leakage control of the optical field. Based on the traditional PCSEL structure (such as CN116316063A), if conventional metal electrodes or planar current spreading layers (ITO) are directly introduced, these high absorption loss media will be closely attached to the photonic crystal layer with high optical field distribution, which will greatly destroy the coherence conditions of the BIC mode, resulting in a sharp drop in Q value, or even quenching of the BIC mode, causing it to degenerate into a normal photonic crystal band-edge mode. (5) Limitations of cladding structure: Existing gallium nitride-based PCSELs (such as CN116316063A) usually use low refractive index layers (such as AlGaN or porous GaN) only as optical cladding to confine the optical field. This structure only provides the confinement of optical waveguide and lacks a strong longitudinal feedback mechanism. Under high power operation, the optical field is prone to leakage to the substrate, and the lack of a longitudinal mode selection mechanism leads to multi-longitudinal mode competition, making it difficult to achieve high-purity single-mode lasing.

[0003] Therefore, there is an urgent need for a new laser structure that can achieve high Q-value lasing using BIC, avoid damage to the active region, and has good heat dissipation and control characteristics. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide a continuous domain bound state laser based on a hybrid cavity structure, which solves the problems of large non-radiative loss, poor heat dissipation, and difficult control caused by active region etching in existing BIC lasers; and provides a method for fabricating this continuous domain bound state laser.

[0005] Technical Solution: The continuous-domain bound-state laser based on a hybrid cavity structure of the present invention comprises, from bottom to top along the vertical direction: a substrate; an optical confinement layer disposed on the substrate; an N-type spacer layer disposed on the optical confinement layer; an active layer disposed on the N-type spacer layer for providing optical gain; a P-type spacer layer disposed on the active layer; a photonic crystal layer disposed on the P-type spacer layer, the photonic crystal layer comprising periodically arranged dielectric structure units; a current spreading layer disposed on the photonic crystal layer; and a nanopore array that spatially penetrates the photonic crystal layer; wherein the optical confinement layer and the photonic crystal layer together constitute a vertical resonant cavity, and the active layer is located within the vertical resonant cavity; the photonic crystal layer is configured to support continuous-domain bound-state modes by the periodic structural parameters of the nanopore array to modulate the emission characteristics of the laser; furthermore, it includes an N-electrode electrically connected to the N-type spacer layer; and a P-electrode electrically connected to the current spreading layer.

[0006] Preferably, the optical confinement layer can be a distributed Bragg reflector (DBR), which utilizes a superlattice structure with alternating high and low refractive indices to provide high reflectivity and enhance longitudinal optical field confinement; it can also be a single-layer porous GaN, which utilizes the lower effective refractive index of porous GaN as a low-refractive-index cladding to limit the light field leakage to the substrate through total internal reflection, thereby effectively confining the light field near the active region. When the optical confinement layer is a superlattice structure with periodically alternating high-refractive-index and low-refractive-index layers, preferably, the high-refractive-index layer is GaN with a thickness of 30 nm-80 nm; the low-refractive-index layer is one of AlInN, AlGaN, or porous GaN, with a thickness of 30 nm-80 nm; and the number of stacking periods is 5-40 pairs. When the optical confinement layer is a single-layer porous GaN layer, it has a lower refractive index than the N-type spacer layer and a thickness of 50 nm-3000 nm, used to provide optical field confinement.

[0007] Preferably, the active layer is a multi-quantum-well structure in which InGaN quantum well layers and GaN barrier layers are periodically stacked; wherein the thickness of the InGaN quantum well layer is 1nm-5nm, and the thickness of the GaN barrier layer is 3nm-20nm; the number of stacking periods of the active layer is 1-15 pairs; and the material composition and structural parameters of the active layer are configured to emit light with a center wavelength in the range of 370nm to 650nm.

[0008] Preferably, the photonic crystal layer is made of GaN and has a thickness of 50nm-300nm; the nanopore array consists of periodically arranged nanopores with a diameter of 30nm-200nm and a depth penetrating the photonic crystal layer; the lattice arrangement of the nanopore array includes one of triangular, quadrilateral, or hexagonal arrangement, with a lattice period of 150nm-300nm; the cross-sectional shape of the nanopores is circular, elliptical, or polygonal; the nanopores are filled with a low-refractive-index medium, which is one of air, silicon oxide (SiO2), or spin-coated glass (SOG). Compared to air holes, filling with a low-refractive-index medium not only maintains sufficient optical refractive index contrast to sustain the BIC mode, but also significantly improves the surface flatness and mechanical strength of the device, prevents foreign matter from entering the holes, and facilitates the smooth deposition of the subsequent current spreading layer.

[0009] Preferably, the current spreading layer is made of indium tin oxide (ITO) or gallium nitride (GaN) and has a thickness of 10 nm to 100 nm; the N-type spacer layer is made of GaN and has a thickness of 100 nm to 1000 nm; the P-type spacer layer is made of GaN and has a thickness of 10 nm to 200 nm; and the substrate is made of gallium nitride, sapphire, silicon, or silicon carbide.

[0010] Preferably, the nanopore array penetrates both the current spreading layer and the photonic crystal layer, giving the current spreading layer a patterned structure consistent with the photonic crystal layer. This through-hole design allows the current spreading layer to have a patterned structure consistent with the photonic crystal, not only achieving uniform current injection into the underlying photonic crystal, but more importantly, the patterned current spreading layer becomes part of the photonic crystal's optical structure, effectively reducing the disruption of BIC mode symmetry by the continuous dielectric layer, thus allowing high-Q BIC modes to persist.

[0011] The method for fabricating a continuous-domain bound-state laser based on a hybrid cavity structure according to the present invention includes the following steps:

[0012] S1: Provide a substrate;

[0013] S2: An optical confinement layer, an N-type spacer layer, an active layer, a P-type spacer layer, and a photonic crystal layer are sequentially grown on the substrate using an epitaxial growth process.

[0014] S3: Perform an etching process on the grown epitaxial wafer to remove a portion of the photonic crystal layer, P-type spacer layer, and active layer, exposing a portion of the surface of the N-type spacer layer to form a mesa structure.

[0015] S4: Deposit a current spreading layer on the photonic crystal layer;

[0016] S5: Using micro-nano fabrication technology, a periodic array of nanopores is etched in the current spreading layer and the photonic crystal layer;

[0017] S6: An N-electrode is fabricated on the exposed N-type spacer layer, and a P-electrode is fabricated on the current spreading layer.

[0018] Preferably, in step S5, micro-nano fabrication technology is used to etch through the current spreading layer and the photonic crystal layer in one go, so that the nanopore array forms a connected pore.

[0019] The method for fabricating a continuous-domain bound-state laser based on a hybrid cavity structure according to the present invention includes the following steps:

[0020] S1: Provide a substrate;

[0021] S2: An optical confinement layer, an N-type spacer layer, an active layer, a P-type spacer layer, and a photonic crystal layer are sequentially grown on the substrate using an epitaxial growth process.

[0022] S3: Perform an etching process on the grown epitaxial wafer to remove a portion of the photonic crystal layer, P-type spacer layer, and active layer, exposing a portion of the surface of the N-type spacer layer to form a mesa structure.

[0023] S4: Using micro-nano fabrication technology, a periodic array of nanopores is etched in the current spreading layer and the photonic crystal layer; silicon oxide (SiO2) or spin-coated glass (SOG) is filled into the nanopore array using atomic layer deposition (ALD), chemical vapor deposition (CVD), or spin coating processes, and the area outside the nanopores is exposed.

[0024] S5: Deposit a current spreading layer on the photonic crystal layer;

[0025] S6: An N-electrode is fabricated on the exposed N-type spacer layer, and a P-electrode is fabricated on the current spreading layer.

[0026] Preferably, in step S2, when the optical confinement layer comprises a porous GaN layer, its preparation process includes first growing a highly doped GaN layer, and then converting it into a porous structure through an electrochemical etching process.

[0027] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0028] 1. Lossless gain and low threshold: The present invention adopts a split design, with the active layer located between the N-type spacer layer and the P-type spacer layer, maintaining the complete layered structure without being etched or destroyed, completely eliminating surface nonradiative recombination loss, preserving the high gain characteristics of the active region, and significantly reducing the threshold current of the laser.

[0029] 2. Surpassing Traditional Cladding Limitations: Unlike existing technologies that only utilize porous GaN as a low-refractive-index cladding for waveguide confinement, this invention utilizes a bottom optical confinement layer (especially a high-reflectivity DBR or a thick-film total internal reflection porous layer) and a top BIC photonic crystal layer to jointly construct a vertical hybrid resonant cavity. The active layer is placed at the standing wave antinode of this hybrid cavity. This structure not only utilizes the BIC principle to achieve large-area coherent oscillation in the transverse direction (high single-mode performance), but also utilizes the longitudinal cavity to achieve strong feedback and strong confinement of the optical field. Compared to traditional structures that rely solely on transverse feedback, the hybrid cavity structure of this invention significantly reduces the threshold current density and increases the photon confinement factor by several times.

[0030] 3. Overcoming the high Q-value-electrical loss paradox of electrically injected BIC lasers: This invention abandons the simple planar ITO covering scheme and innovatively adopts a nanopore array structure that penetrates the photonic crystal and the current spreading layer. Unlike the island electrodes or conventional planar ITO of the prior art, the patterned current spreading layer of this invention is highly coupled to the photonic crystal lattice. On the one hand, the presence of the ITO layer solves the current congestion problem caused by the low lateral conductivity of the P-type layer in wide bandgap semiconductors; on the other hand, the patterned ITO layer actually participates in the modulation of the BIC mode, avoiding the destruction of BIC coherence by the continuous absorption layer.

[0031] 4. Flexible control: The optical field control structure (photonic crystal layer) is physically separated from the gain medium (active layer), allowing the laser wavelength and emission angle to be controlled simply by changing the pattern design of the photonic crystal without changing the epitaxial process of the active region. Attached Figure Description

[0032] Figure 1 This is a schematic cross-sectional view of a continuous domain bound state laser based on a hybrid cavity structure provided in Embodiment 1 of the present invention.

[0033] Figure 2 This is a schematic cross-sectional view of the DBR layer in Embodiment 1 of the present invention.

[0034] Figure 3 This is a top view of the photonic crystal layer and nanopore array in Embodiment 1 of the present invention.

[0035] Figure 4 This is the reflection spectrum of the DBR layer in Embodiment 1 of the present invention.

[0036] Figure 5 This is a top view of the photonic crystal layer and nanopore array in Embodiment 1 of the present invention.

[0037] Figure 6 This is a cross-sectional view of the porous DBR layer in Embodiment 2 of the present invention.

[0038] Figure 7 This is a schematic diagram of a cross-sectional scanning electron microscope (SEM) image of a gallium nitride porous DBR-based BIC laser prepared in Example 3 of the present invention.

[0039] Figure 8 This is a simulation comparison chart of the quality factor Q values ​​of the hybrid cavity structure and the structure without DBR in Embodiment 3 of the present invention.

[0040] Figure 9 The laser prepared in Example 3 of this invention is shown as a lasing spectrum evolution diagram under different injection intensities.

[0041] Figure 10 The laser prepared in Example 4 of this invention has different lasing spectra under different parameter configurations. Detailed Implementation

[0042] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0043] Example 1: GaN-based hybrid cavity BIC laser

[0044] like Figure 1 As shown, this embodiment provides a continuous-domain confined-state laser based on a hybrid cavity structure, with the following structural parameters: Stacked structure: Substrate 1: GaN substrate. Optical confinement layer 2: Distributed Bragg mirror layer: disposed on the substrate. N-type spacer layer 3: made of silicon-doped N-type GaN, with a thickness of 1000 nm, used to provide stable electron injection and serve as a contact layer for the N-electrode. Active layer 4: InGaN / GaN multiple quantum well (MQW) structure. Contains 15 cycles of InGaN quantum wells (5 nm thick) and GaN barrier layers (20 nm thick), used to provide optical gain in the 350 nm to 650 nm wavelength range. P-type spacer layer 5: made of magnesium-doped P-type GaN, with a thickness of 200 nm, used for hole transport and to isolate the active region. Photonic crystal layer 6: made of P-type GaN, with a thickness of 300 nm. Current spreading layer 7: made of indium tin oxide (ITO), with a thickness of 100 nm, deposited on the surface of the photonic crystal layer to enhance current spreading.

[0045] The nanopore array 8 was fabricated using electron beam lithography (EBL) and dry etching processes. The nanopores spatially penetrate both the current spreading layer 7 and the photonic crystal layer 6, reaching the interface of the P-type spacer layer 5.

[0046] Parameter configuration: The optical confinement layer 2 is formed by periodically alternating growth of AlInN or AlGaN (low refractive index, thickness 20-110nm) and GaN (high refractive index, thickness 20-110nm), with 5-40 pairs of cycles. A schematic diagram of the cross-sectional structure is shown below. Figure 2As shown. The center reflection wavelength of this DBR layer is designed to meet the wavelength range of 350-650nm, with a reflectivity greater than 99%; as Figure 4 As shown, the reflection spectrum curves generated by continuously varying the thickness of the high and low refractive index layers within the range of 20 nm to 110 nm are illustrated, matching the high and low refractive index layer thickness and luminescence range described in this invention. Figure 5 As shown, the experimentally prepared nanopores are arranged in a quadrilateral lattice with a lattice period ranging from 180 nm to 260 nm and a pore diameter of 70-100 nm. By fine-tuning the geometry of the pores (e.g., by introducing extremely small ellipticity), the in-plane symmetry is broken, supporting quasi-BIC modes and enabling single-mode lasing in the vertical direction.

[0047] Example 2: Hybrid Cavity BIC Laser Based on Porous GaN DBR

[0048] This embodiment focuses on illustrating the structure and preparation method of using porous GaN as the DBR layer.

[0049] Structural differences: Unlike Example 1, the optical confinement layer 2 adopts a GaN / porous GaN superlattice structure. High refractive index layer: Undoped GaN, thickness 20-110 nm. Low refractive index layer: Porous GaN formed by electrochemical etching of highly doped GaN, with a porosity of approximately 20-40%, resulting in a reduced equivalent refractive index, thickness 20-110 nm.

[0050] Preparation method:

[0051] S1: Provides a GaN buffer layer substrate.

[0052] S2: Using MOCVD technology, a stack of highly doped GaN and undoped GaN layers (for subsequent DBR fabrication), an N-type spacer layer 3, an InGaN / GaN active layer 4, a P-type spacer layer 5, and a GaN photonic crystal layer 6 are sequentially grown on the substrate. Note: For porous GaN DBRs, electrochemical etching (EC) is performed after this step to convert the highly doped GaN layer into a porous layer, such as... Figure 6 As shown in the actual product image.

[0053] S3: Using inductively coupled plasma (ICP) etching, the photonic crystal layer, P-type spacer layer and active layer in the edge region are removed, reaching the interior of the N-type spacer layer 3 to expose the N-type mesa.

[0054] S4: An ITO thin film with a thickness of 10-100 nm is deposited on the surface of the photonic crystal layer 6 by magnetron sputtering and rapid thermal annealing (RTA) is performed to form an ohmic contact as the current spreading layer 7.

[0055] S5: Apply resist and define the photonic crystal pattern using electron beam lithography (EBL). ICP dry etching is then performed using a Cl2 / BCl3 / Ar mixed gas to penetrate both the ITO layer and the GaN photonic crystal layer in a single pass, forming a nanopore array 8. This process ensures perfect alignment of the pores in the ITO layer with the underlying GaN layer.

[0056] S6: Using electron beam evaporation, N-electrode 9 and P-electrode 10 are deposited on the exposed N-type mesa and ITO layer, respectively.

[0057] Example 3: Device Fabrication and Performance Verification

[0058] To verify the feasibility and superiority of the technical solution of the present invention, the inventors actually prepared a hybrid cavity BIC laser based on porous GaN DBR according to the preparation method of Example 2 above, and performed structural characterization and photoelectric performance testing.

[0059] Cross-sectional structural characterization: such as Figure 7 The image shows a scanning electron microscope (SEM) image of the experimentally fabricated laser cross-section. The optical confinement layer 2 at the bottom is clearly visible, exhibiting a superlattice structure with alternating light and dark areas. The brighter areas are the high-refractive-index layer 11 (GaN), while the darker areas with micropores are the low-refractive-index layer 12 (porous GaN). The porous DBR layer has a clear and smooth interface with uniform pore distribution, confirming the high controllability of the electrochemical etching process. Above the DBR layer, the N-type spacer layer 3, InGaN / GaN active layer 4, P-type spacer layer 5, and the top GaN photonic crystal layer 6 form a complete layered structure with steep interfaces. Notably, the top layer features a nanopore array penetrating the photonic crystal layer, and the current spreading layer 7 uniformly covers the etched area, confirming the successful fabrication of the "through-type" electrode structure.

[0060] Simulation Verification: To verify the enhancement effect of the hybrid cavity design on the BIC mode, we established a three-dimensional simulation model using the finite-difference time-domain (FDTD) method and calculated the mode quality factor (Q value) under different cavity structures. Figure 8 As shown, the Q-value distributions of the traditional structure (with only a top photonic crystal, no bottom DBR) and the hybrid cavity structure of this invention (with a porous GaN DBR at the bottom) are compared. Results analysis: In the structure without a DBR, the optical field leaks significantly into the substrate, limiting the improvement in Q-value. However, after introducing a porous GaN DBR to construct a vertical hybrid resonant cavity, the optical field is strongly confined in the vertical direction, resulting in strong coupling with the lateral BIC mode. Simulation results show that the resonant mode Q-value of the structure of this invention is improved by three orders of magnitude (more than 10) compared to the traditional structure. 9 (on a scale of magnitude). This significant improvement directly confirms the core advantages of the hybrid cavity design in reducing optical loss and enhancing the interaction between light and matter.

[0061] Experimental verification: The fabricated device underwent electrical injection variable power testing at room temperature, such as... Figure 9 As shown, the evolution of the device's emission spectrum under different injection power densities is illustrated. As the injection current increases to near the threshold, a distinct peak appears in the spectral center, indicating the onset of mode competition and the gradual overcoming of losses by the gain. When the injection current exceeds the threshold, the spectrum narrows rapidly, exhibiting an extremely narrow single-mode lasing peak at 472 nm. At this point, the side-mode suppression ratio (SMSR) exceeds 25 dB, and the full width at half maximum (FWHM) is less than 0.1 nm.

[0062] This embodiment demonstrates that the hybrid cavity BIC laser proposed in this invention can achieve stable single-mode lasing and has a low lasing threshold, verifying its feasibility in practical optoelectronic applications.

[0063] Example 4: Extension of structural parameters for hybrid cavity BIC laser

[0064] To further verify the applicability of the technical solution of the present invention in a wide spectral range and the controllability of the structural parameters, the inventors, based on the preparation method described in Example 2, prepared multiple sets of hybrid cavity BIC lasers with different lasing wavelengths by adjusting the superlattice period thickness of the DBR layer and the lattice constant of the photonic crystal layer, and conducted laser spectral tests.

[0065] Test results are as follows Figure 10 As shown, the specific experimental data are as follows:

[0066] Blue light band verification (445nm): When the sum of the thicknesses of the high-refractive-index and low-refractive-index layers in the DBR layer (i.e., the stacking period) is controlled within the range of 85nm to 95nm (including but not limited to the following combination: porous GaN thickness 40nm, GaN layer thickness 50nm), the center reflection wavelength of the fabricated DBR layer is approximately 445nm. At this time, a photonic crystal layer with a lattice period of 190nm is then fabricated. Test results show that this device achieves single-mode laser lasing with a center wavelength of 445nm.

[0067] Cyan band verification (475nm): When the sum of the thicknesses of the high and low refractive index layers of the DBR layer is increased to the range of 95nm to 105nm (including but not limited to the following combinations: porous GaN thickness 50nm, GaN layer thickness 50nm), the central reflection wavelength of the DBR layer redshifts to approximately 475nm. Correspondingly, the lattice period of the photonic crystal layer is adjusted to 210nm. Test results show that the device successfully achieved laser lasing with a center wavelength of 475nm.

[0068] Green light band verification (510nm): When the sum of the thicknesses of the high and low refractive index layers of the DBR layer is further increased to the range of 105nm to 115nm (including but not limited to the following combinations: porous GaN thickness 50nm, GaN layer thickness 60nm), the center reflection wavelength of the DBR layer is approximately 510nm. At this point, a photonic crystal layer with a lattice period of 225nm is fabricated. Test results show that this device achieves laser lasing with a center wavelength of 510nm.

[0069] The experimental results above demonstrate that the hybrid cavity BIC laser structure proposed in this invention exhibits excellent parameter scalability. A clear positive linear correlation exists between the lasing wavelength of the device and the periodic thickness of the DBR layer and the lattice period of the photonic crystal.

[0070] This experimental fact powerfully proves that: (1) the present invention has successfully covered the visible light band from 440nm to 510nm in experiments; (2) based on Maxwell's equations in electromagnetic field theory and the scaling law of photonic crystals, those skilled in the art can reasonably predict that by further reducing or increasing the above structural parameters (DBR layer thickness and photonic crystal period) proportionally, the lasing wavelength can be extended to ultraviolet (350nm direction) or red light (650nm direction).

[0071] Therefore, the experimental data in this embodiment fully support the limitations of the present invention regarding the range of high and low refractive index layer thicknesses and the range of photonic crystal lattice parameters, proving the feasibility and rationality of the present invention in achieving laser generation in the full visible light band from 350nm to 650nm.

Claims

1. A continuous-domain bound-state laser based on a hybrid cavity structure, characterized in that, The structure comprises, from bottom to top, the following components in a vertical direction: a substrate (1); an optical confinement layer (2) disposed on the substrate (1); an N-type spacer layer (3) disposed on the optical confinement layer (2); an active layer (4) disposed on the N-type spacer layer (3) for providing optical gain; a P-type spacer layer (5) disposed on the active layer (4); a photonic crystal layer (6) disposed on the P-type spacer layer (5), the photonic crystal layer (6) comprising periodically arranged dielectric structure units; a current spreading layer (7) disposed on the photonic crystal layer (6); and a nanometer layer. A nanopore array (8) spatially penetrates the photonic crystal layer (6); wherein the optical confinement layer (2) and the photonic crystal layer (6) together form a vertical resonant cavity, and the active layer (4) is located within the vertical resonant cavity; the photonic crystal layer (6) is configured to support continuous domain bound state modes through the periodic structural parameters of the nanopore array (8) to modulate the emission characteristics of the laser; in addition, it also includes an N electrode (9) electrically connected to the N-type spacer layer (3); and a P electrode (10) electrically connected to the current spreading layer (7).

2. The continuous-domain bound-state laser based on a hybrid cavity structure according to claim 1, characterized in that, The optical confinement layer (2) is selected from either a distributed Bragg mirror (DBR) or a single-layer porous GaN layer; When the optical confinement layer (2) is a distributed Bragg reflector (DBR), it is a superlattice structure in which a high refractive index layer (11) and a low refractive index layer (12) are periodically stacked alternately; wherein, the high refractive index layer (11) is GaN with a thickness of 30nm-80nm; the low refractive index layer (12) is one of AlInN, AlGaN or porous GaN with a thickness of 30nm-80nm; the number of stacking periods is 5-40 pairs; When the optical confinement layer (2) is a single-layer porous GaN layer, it has a lower refractive index than the N-type spacer layer (3) and a thickness of 50nm-3000nm, and is used to provide optical field confinement.

3. The continuous-domain bound-state laser based on a hybrid cavity structure according to claim 1, characterized in that, The active layer (4) is a multi-quantum-well structure consisting of a periodically stacked InGaN quantum well layer and a GaN barrier layer; wherein the thickness of the InGaN quantum well layer is 1nm-5nm and the thickness of the GaN barrier layer is 3nm-20nm; the number of stacking periods of the active layer (4) is 1-15 pairs; the material composition and structural parameters of the active layer (4) are configured to emit light with a center wavelength in the range of 370nm to 650nm.

4. The continuous-domain bound-state laser based on a hybrid cavity structure according to claim 1, characterized in that, The photonic crystal layer (6) is made of GaN and has a thickness of 50nm-300nm. The nanopore array (8) is composed of periodically arranged nanopores with a diameter of 30nm-200nm and a depth penetrating the photonic crystal layer (6). The lattice arrangement of the nanopore array (8) includes one of triangular, quadrilateral, or hexagonal arrangement, with a lattice period of 150nm-300nm. The cross-sectional shape of the nanopores is circular, elliptical, or polygonal. The nanopores are filled with a low-refractive-index medium, which is one of air, silicon oxide (SiO2), or spin-coated glass (SOG).

5. The continuous-domain bound-state laser based on a hybrid cavity structure according to claim 1, characterized in that, The current spreading layer (7) is made of indium tin oxide (ITO) or gallium nitride (GaN) and has a thickness of 10nm-100nm; the N-type spacer layer (3) is made of GaN and has a thickness of 100nm-1000nm; the P-type spacer layer (5) is made of GaN and has a thickness of 10nm-200nm; the substrate (1) is made of gallium nitride, sapphire, silicon, or silicon carbide.

6. The continuous-domain bound-state laser based on a hybrid cavity structure according to claim 1, characterized in that, The nanopore array (8) penetrates both the current spreading layer (7) and the photonic crystal layer (6), so that the current spreading layer (7) has a patterned structure consistent with the photonic crystal layer (6).

7. A method for fabricating a continuous-domain bound-state laser based on a hybrid cavity structure as described in claim 1, characterized in that, Includes the following steps: S1: Provide a substrate (1); S2: An optical confinement layer (2), an N-type spacer layer (3), an active layer (4), a P-type spacer layer (5), and a photonic crystal layer (6) are sequentially grown on the substrate (1) using an epitaxial growth process. S3: The epitaxial wafer that has been grown is etched to remove part of the photonic crystal layer (6), the P-type spacer layer (5) and the active layer (4), exposing part of the surface of the N-type spacer layer (3) to form a mesa structure; S4: Deposit a current spreading layer (7) on the photonic crystal layer (6); S5: Using micro-nano fabrication technology, a periodic array of nanopores (8) is formed by etching in the current spreading layer (7) and the photonic crystal layer (6). S6: An N electrode (9) is prepared on the exposed N-type spacer layer (3), and a P electrode (10) is prepared on the current spreading layer (7).

8. The preparation method according to claim 7, characterized in that, In step S5, micro-nano fabrication technology is used to etch through the current extension layer (7) and the photonic crystal layer (6) in one go, so that the nanopore array (8) forms a connected hole.

9. A method for fabricating a continuous-domain bound-state laser based on a hybrid cavity structure as described in claim 1, characterized in that, Includes the following steps: S1: Provide a substrate (1); S2: An optical confinement layer (2), an N-type spacer layer (3), an active layer (4), a P-type spacer layer (5), and a photonic crystal layer (6) are sequentially grown on the substrate (1) using an epitaxial growth process. S3: The epitaxial wafer that has been grown is etched to remove part of the photonic crystal layer (6), the P-type spacer layer (5) and the active layer (4), exposing part of the surface of the N-type spacer layer (3) to form a mesa structure; S4: Using micro-nano fabrication technology, a periodic nanopore array (8) is formed by etching in the current spreading layer (7) and the photonic crystal layer (6); silicon oxide (SiO2) or spin-coated glass (SOG) is filled into the nanopore array (8) by atomic layer deposition (ALD), chemical vapor deposition (CVD) or spin coating process, and the area outside the nanopores is exposed. S5: Deposit a current spreading layer (7) on the photonic crystal layer (6); S6: An N electrode (9) is prepared on the exposed N-type spacer layer (3), and a P electrode (10) is prepared on the current spreading layer (7).

10. The preparation method according to claim 7 or 9, characterized in that, In step S2, when the optical confinement layer (2) contains a porous GaN layer, its preparation process includes first growing a highly doped GaN layer, and then converting it into a porous structure through an electrochemical etching process.

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