A vertical cavity surface emitting laser

Abstract

The application discloses a vertical cavity surface emitting laser. The vertical cavity surface emitting laser comprises a plurality of light emitting units, the light emitting units are provided with light emitting areas, and the light emitting areas of at least partially adjacent light emitting units are overlapped. The technical scheme provided by the embodiment of the application reduces the planar size of the vertical cavity surface emitting laser.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more particularly to a vertical cavity surface-emitting laser. Background Technology

[0002] Vertical cavity surface emitting lasers (VCSELs) are increasingly widely used due to their advantages such as small size, low threshold current, high modulation frequency, and easy fiber coupling.

[0003] There is an urgent need for a vertical cavity surface-emitting laser with a very small planar size while maintaining a fixed optical power. Summary of the Invention

[0004] This invention provides a vertical cavity surface-emitting laser (VCSEL) to reduce the planar size of VCSELs.

[0005] According to one aspect of the present invention, a vertical-cavity surface-emitting laser is provided, comprising:

[0006] Multiple light-emitting units,

[0007] The light-emitting unit is provided with a light-emitting area, and the light-emitting areas of at least some adjacent light-emitting units overlap.

[0008] Optionally, the vertical-cavity surface-emitting laser includes a substrate;

[0009] A first electrode, the first electrode being located on a first surface of the substrate;

[0010] The light-emitting unit includes a stack of a first Bragg reflector, an active layer, and a second Bragg reflector, wherein the first Bragg reflector is located on a second surface of the substrate opposite to the first surface;

[0011] An ohmic contact layer is located on the surface of the second Bragg mirror away from the active layer;

[0012] An oxide trench is provided around the light-emitting unit. An oxide layer is provided between the second Bragg reflector and the active layer. The oxide layer forms an oxide hole, and the light emitted by the light-emitting unit passes through the oxide hole to form the light-emitting area.

[0013] The second electrode is located at the edge of the light-emitting unit and surrounds the light-emitting area, and is used to define the light-emitting area. The second electrodes of two overlapping light-emitting units in the light-emitting area are either continuously or discontinuously arranged at the overlap.

[0014] Optionally, the second electrodes of two overlapping light-emitting units in the light-emitting area may be continuously or discontinuously arranged at the non-overlapping locations.

[0015] Optionally, the vertical cavity surface-emitting laser further includes a second electrode connection pad, which connects to the second electrodes of at least two light-emitting units.

[0016] Optionally, the vertical cavity surface-emitting laser further includes a passivation layer covering the oxide trench and the ohmic contact layer, and the passivation layer is provided with a via, the via exposing the middle region of the second electrode.

[0017] Optionally, in a light-emitting unit, the orthogonal projection of the oxide hole onto the substrate is within the orthogonal projection of the substrate in the area enclosed by the second electrode.

[0018] Optionally, the contour of the oxide pores includes arcs and / or straight lines.

[0019] Optionally, the outline of the light-emitting area includes arcs and / or straight lines.

[0020] Optionally, at least two light-emitting units may share a common oxide trench.

[0021] Optionally, the oxide trench surrounding a light-emitting unit may include multiple discontinuous sub-oxide trenches.

[0022] Optionally, the vertical cavity surface-emitting laser further includes an ion implantation layer located above the active layer via the second Bragg mirror from the ohmic contact layer.

[0023] The oxide layer includes a first oxide layer and a second oxide layer. The sub-oxide trenches corresponding to the first oxide layer and the sub-oxide trenches corresponding to the second oxide layer are adjacent but discontinuous sub-oxide trenches of the same light-emitting unit.

[0024] The orthogonal projection of the ion implanted layer onto the substrate connects to or covers a portion of the orthogonal projection of the first portion of the oxide layer onto the substrate, and connects to or covers a portion of the orthogonal projection of the second portion of the oxide layer onto the substrate.

[0025] The current path is confined by the region enclosed by the oxide layer and the ion implantation layer, and light is emitted in the active layer and then emitted from the light-emitting region.

[0026] Optionally, the oxide layer further includes at least one pair of third oxide layers and fourth oxide layers, wherein the sub-oxide trenches corresponding to the third oxide layer and the sub-oxide trenches corresponding to the fourth oxide layer are adjacent and discontinuous sub-oxide trenches of the same light-emitting unit.

[0027] The region between the orthographic projection of the ion implanted layer on the substrate and the region between the third partial oxide layer and the fourth partial oxide layer on the substrate do not overlap in the orthographic projection of the substrate.

[0028] The region between the third oxide layer and the fourth oxide layer is the light-emitting region.

[0029] Optionally, the vertical cavity surface-emitting laser further includes a second electrode connection pad, which is connected to the second electrode;

[0030] The second electrode connection pad includes an overlapping portion pad, wherein the orthographic projection of the overlapping portion pad on the substrate overlaps with the orthographic projection of the ion implanted layer on the substrate, and the orthographic projection of the overlapping portion pad on the substrate is located within the orthographic projection of the ion implanted layer on the substrate.

[0031] The overlapping portion of the pads overlaps with the orthographic projection of the oxide layer corresponding to the discontinuous sub-oxide trench on the substrate, and the orthographic projection of the overlapping portion of the pads on the substrate is located within the orthographic projection of the oxide layer corresponding to the discontinuous sub-oxide trench on the substrate.

[0032] Optionally, the length of the region between at least one pair of the third partial oxide layer and the fourth partial oxide layer in the plane of the substrate is the maximum length of the light-emitting region in the plane of the substrate.

[0033] Optionally, the cross-sectional shape of the oxide layer corresponding to the discontinuous sub-oxide trenches in the plane of the substrate is a symmetrical shape.

[0034] In the technical solution provided in this embodiment, the light-emitting areas of at least some adjacent light-emitting units overlap, which can reduce the distance between light-emitting units and thus reduce the planar size of the vertical cavity surface-emitting laser.

[0035] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1This is a top view of a vertical cavity surface-emitting laser provided according to an embodiment of the present invention;

[0038] Figure 2 yes Figure 1 An enlarged view of region S1 in the middle;

[0039] Figure 3 Section lines A1-A2 and B1-B2 are respectively located at... Figure 1 A schematic diagram of the section position in the structure shown;

[0040] Figure 4 yes Figure 3 A schematic diagram of the cross-sectional structure along section line A1-A2;

[0041] Figure 5 yes Figure 3 A schematic diagram of the cross-sectional structure along section line B1-B2;

[0042] Figure 6 It is the section line C1-C2 at Figure 1 A schematic diagram of the section position in the structure shown;

[0043] Figure 7 yes Figure 6 A schematic diagram of the cross-sectional structure along section line C1-C2;

[0044] Figure 8 It is the S2 region. Figure 1 A schematic diagram showing the location from a top-down view;

[0045] Figure 9 yes Figure 8 An enlarged view of region S2 in the middle;

[0046] Figure 10 yes Figure 8 Another magnified view of region S2 in the middle;

[0047] Figure 11 yes Figure 10 An enlarged view of one of the light-emitting units;

[0048] Figure 12 This is a schematic diagram of a structure provided by an embodiment of the present invention, in which the second electrodes of two light-emitting units with overlapping light-emitting areas are discontinuously arranged;

[0049] Figure 13 It is in the S3 area Figure 1 A schematic diagram showing the location in the top view;

[0050] Figure 14 yes Figure 13 An enlarged view of region S3 in the middle;

[0051] Figure 15It is in the S4 area Figure 1 A schematic diagram showing the location in the top view;

[0052] Figure 16 yes Figure 15 A magnified view of an oxide layer in the S4 region of the middle section;

[0053] Figure 17 yes Figure 16 A magnified view of the oxide layer corresponding to one of the light-emitting units;

[0054] Figure 18 This is a top view of another vertical cavity surface-emitting laser provided according to an embodiment of the present invention;

[0055] Figure 19 yes Figure 18 A magnified view of an ion implantation layer in the S5 region of the middle S5 region;

[0056] Figure 20 yes Figure 18 A magnified view of an ion implantation layer and an oxide layer in the S5 region of the middle S5 region;

[0057] Figure 21 yes Figure 18 An enlarged view of a second electrode connection pad in the S5 region;

[0058] Figure 22 yes Figure 18 An enlarged view of an ion implantation layer, an oxide layer, and a second electrode connection pad in the S5 region;

[0059] Figure 23 This is a schematic diagram of an oxide layer according to an embodiment of the present invention. Detailed Implementation

[0060] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0061] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0062] To reduce the planar dimensions of vertical-cavity surface-emitting lasers (VCSELs), embodiments of the present invention provide the following technical solutions:

[0063] See Figure 1 and Figure 2 , Figure 1 This is a top view of a vertical-cavity surface-emitting laser provided according to an embodiment of the present invention. Figure 2 yes Figure 1 An enlarged view of region S1 in the image shows that the vertical cavity surface-emitting laser includes: a plurality of light-emitting units 1, each light-emitting unit 1 having a light-emitting area 10, and at least some of the light-emitting areas 10 of adjacent light-emitting units 1 overlapping.

[0064] For example, Figure 1 In the middle, the light-emitting areas 10 of two adjacent light-emitting units 1 in the same row overlap.

[0065] In the technical solution provided in this embodiment, the light-emitting areas 10 of at least some adjacent light-emitting units 1 overlap, which can reduce the distance between light-emitting units 1, thereby reducing the planar size of the vertical cavity surface-emitting laser.

[0066] Optionally, based on the above technical solutions, see [reference needed]. Figures 3-7The vertical-cavity surface-emitting laser includes a substrate 001 (e.g., an N-type substrate); a first electrode 002 (e.g., N metal), the first electrode 002 being located on a first surface of the substrate 001; and a light-emitting unit 1 including a first Bragg mirror 003 (N... A stack of a first Bragg reflector (DBR), an active layer (QW), and a second Bragg reflector (PDBR), wherein the first Bragg reflector (003) is located on the second surface of the substrate (001) opposite to the first surface; an ohmic contact layer (006) is located on the surface of the second Bragg reflector (005) away from the active layer (004); an oxide trench (T1) is disposed around the light-emitting unit (1), and an oxide layer (50) is disposed between the second Bragg reflector (005) and the active layer (004), the oxide layer (50) forming an oxide hole, and the light emitted by the light-emitting unit (1) passes through the oxide hole to form a light-emitting region (10); a second electrode (007) is located at the edge of the light-emitting unit (1), the second electrode (007) is disposed around the light-emitting region (10) and is used to define the light-emitting region (10), and the second electrodes (007) of two overlapping light-emitting units (1) are disposed continuously or discontinuously at the overlap.

[0067] For example, see Figure 8 and Figure 9 The two light-emitting units 1 have an overlapping region Q1. See [link / reference] Figure 10 and Figure 11 as well as Figure 2 In the light-emitting region 10, the second electrodes 007 of the two overlapping light-emitting units 1 are continuously arranged at the overlap. That is, the second electrodes 007 of the two overlapping light-emitting units 1 are interconnected.

[0068] See Figure 12 In the light-emitting area 10, the second electrodes 007 of the two overlapping light-emitting units 1 can be discontinuously arranged at the overlapping point. That is, the second electrodes 007 of the two overlapping light-emitting units 1 are disconnected.

[0069] Specifically, under the electric field of the first electrode 002 and the second electrode 007, the second electrodes 007 of the two overlapping light-emitting units 1 in the light-emitting region 10 can be continuously or discontinuously arranged at the overlap. Charge carriers move, recombine, and emit light. The current path is limited by the oxide holes formed by the oxide layer 50, and light is emitted in the active layer before exiting from the light-emitting region 10. Therefore, the second electrodes 007 of the two overlapping light-emitting units 1 in the light-emitting region 10 can be discontinuously arranged, thus saving the area of ​​the second electrode 007 and increasing the area of ​​the light-emitting region 10.

[0070] Optionally, based on the above technical solution, the second electrodes 007 of the two overlapping light-emitting units 1 in the light-emitting area 10 are either continuously or discontinuously arranged at the non-overlapping locations.

[0071] For example, see Figure 10 , Figure 11 and Figure 2 In this embodiment, except for the overlapping area Q1, the second electrode 007 of the light-emitting unit 1 is also continuously disposed. In the accompanying drawings of this embodiment, the second electrodes 007 of the two overlapping light-emitting units 1 in the light-emitting area 10 are continuously disposed at the non-overlapping areas. In other embodiments, see... Figure 12 In addition to the overlapping area Q1, the second electrodes 007 of the two overlapping light-emitting units 1 in the light-emitting area 10 can also be discontinuously arranged in the non-overlapping areas, thereby saving the area of ​​the second electrode 007 and increasing the area of ​​the light-emitting area 10.

[0072] Optionally, based on the above technical solutions, see [reference needed]. Figure 4 , Figure 5 and Figure 7 as well as Figure 13 and Figure 14 The vertical cavity surface-emitting laser also includes a second electrode connection pad 009 (Pad metal), which connects to the second electrodes 007 of at least two light-emitting units 1.

[0073] Specifically, the second electrodes 007 of multiple light-emitting units 1 can be connected in series through the second electrode connection pad 009, so that the second electrodes 007 of multiple light-emitting units 1 can obtain the same electrical signal through a second electrode connection pad 009.

[0074] Optionally, based on the above technical solutions, see [reference needed]. Figure 4 and Figure 5 The vertical cavity surface-emitting laser also includes a passivation layer 008, which covers the oxide trench T1 and the ohmic contact layer 006, and the passivation layer 008 is provided with a through hole 80, which exposes the middle region of the second electrode 007.

[0075] It should be noted that, Figure 4 and Figure 5 The edge area of ​​the second electrode 007 covered by the passivation layer 008 is not shown in the figure, but in the actual setup process, the area of ​​the second electrode 007 is larger than the area of ​​the second electrode 007 exposed by the through hole 80.

[0076] Optionally, based on the above technical solutions, see [reference needed]. Figure 10 , Figure 11 , Figure 16 as well as Figure 17 In a light-emitting unit 1, the orthogonal projection of the oxide hole onto the substrate 001 is within the orthogonal projection of the substrate 001 in the area enclosed by the second electrode 007.

[0077] Under the electric field of the first electrode 002 and the second electrode 007, charge carriers move, recombine, and emit light. The current path is limited by the oxide holes enclosed by the oxide layer 50, and light is emitted in the active layer and then emitted from the light-emitting region 10. The area of ​​the light-emitting region 10 is larger than the area of ​​the oxide holes enclosed by the oxide layer 50. The oxide holes are the areas enclosed by the oxide layer 50, and the area enclosed by the second electrode 007 is used to define the light-emitting region 10. In a light-emitting unit 1, the orthographic projection of the oxide holes on the substrate 001 is within the orthographic projection of the area enclosed by the second electrode 007, that is, the distance L1 between the oxide range of the oxide layer 50 and the second electrode 007 is greater than or equal to a minimum distance. This minimum distance is within a preset value range, which can ensure that the area of ​​the light-emitting region 10 is larger than the area of ​​the oxide holes enclosed by the oxide layer 50.

[0078] Optionally, based on the above technical solution, the contour of the oxide pore includes arcs and / or straight lines.

[0079] It should be noted that in a light-emitting unit 1, the orthogonal projection of the oxide hole on the substrate 001 is within the area enclosed by the second electrode 007. That is, the distance L1 between the oxide range of the oxide layer 50 and the second electrode 007 is greater than or equal to the minimum distance. This minimum distance is within a preset value range, which can ensure that the area of ​​the light-emitting area 10 is greater than the area of ​​the oxide hole enclosed by the oxide layer 50.

[0080] The outline of the oxide pores enclosed by the oxide layer 50 can be regular or irregular. See also Figure 10 , Figure 11 , Figures 15-17 The outline of the oxide pores enclosed by the oxide layer 50 is irregular, with some parts being straight lines and others being curved lines, which allows the shape of the outline of the oxide pores enclosed by the oxide layer 50 to be irregular.

[0081] Optionally, based on the above technical solution, the outline of the light-emitting area 10 includes arcs and / or straight lines.

[0082] It should be noted that in a light-emitting unit 1, the orthogonal projection of the oxide hole on the substrate 001 is within the area enclosed by the second electrode 007. That is, the distance L1 between the oxide range of the oxide layer 50 and the second electrode 007 is greater than or equal to the minimum distance. This minimum distance is within a preset value range, which can ensure that the area of ​​the light-emitting area 10 is greater than the area of ​​the oxide hole enclosed by the oxide layer 50.

[0083] The outline of the light-emitting area 10 can be regular or irregular.

[0084] See Figure 14 The shape of the outline of the light-emitting area 10 defined by the second electrode 007 can be regular, and the outline is enclosed by an arc. See also Figure 17 The shape of the outline of the light-emitting area 10 defined by the second electrode 007 can be irregular, with some parts being straight lines and others being curved lines.

[0085] Optionally, based on the above technical solution, at least two light-emitting units share a common oxide trench.

[0086] See Figure 9 At least two light-emitting units 1 share a common oxide trench T1, which can reduce the area of ​​the oxide trench T1, thereby reducing the planar size of the vertical cavity surface-emitting laser.

[0087] Optionally, based on the above technical solution, the oxide trench surrounding a light-emitting unit includes multiple discontinuous sub-oxide trenches.

[0088] For details, see Figure 9 The oxide trench T1 surrounding a light-emitting unit 1 includes multiple discontinuous sub-oxide trenches, which further reduces the area of ​​the oxide trench T1, thereby reducing the planar size of the vertical cavity surface-emitting laser.

[0089] Optionally, based on the above technical solutions, refer to Figures 18-22 , combined Figure 3 and Figure 4 The vertical cavity surface-emitting laser also includes an ion implantation layer 60, which is located above the active layer 004 via the ohmic contact layer 006 and the second Bragg mirror 005.

[0090] The oxide layer 50 includes a first oxide layer 51 and a second oxide layer 52. The sub-oxide trenches corresponding to the first oxide layer 51 and the sub-oxide trenches corresponding to the second oxide layer 52 are adjacent and discontinuous sub-oxide trenches of the same light-emitting unit 1.

[0091] The orthogonal projection of the ion implantation layer 60 onto the substrate 001 connects to or covers the orthogonal projection of the first oxide layer 51 onto the substrate 001, and connects to or covers the orthogonal projection of the second oxide layer 52 onto the substrate 001.

[0092] The current path is confined by the region enclosed by the oxide layer 50 and the ion implantation layer 60, and light is emitted in the active layer 004 and then emitted from the light-emitting region 10.

[0093] Specifically, if the size of the oxidized oxide layer 50 on the light-emitting side is insufficient for the second electrode connection pad 009 to connect the second electrodes 007 of each light-emitting unit 1, an insulating process can be added below the connection area of ​​the second electrode connection pad 009. The insulating process can be an ion implantation process, injecting ions into the area where the oxide layer 50 is insufficient to form an ion implantation layer 60. This limits the current path by the area enclosed by the oxide layer 50 and the ion implantation layer 60, thus solving the problem of insufficient oxide layer 50 after oxidation.

[0094] Optionally, the oxide layer further includes at least one pair of third oxide layers and fourth oxide layers, wherein the sub-oxide trenches corresponding to the third oxide layer and the sub-oxide trenches corresponding to the fourth oxide layer are adjacent and discontinuous sub-oxide trenches of the same light-emitting unit.

[0095] The orthographic projection of the ion implanted layer onto the substrate does not overlap with the orthographic projection of the third oxide layer and part of the fourth oxide layer onto the substrate.

[0096] The region between the third oxide layer and part of the fourth oxide layer is the luminescent region.

[0097] For example, refer to Figure 18 Region S6 is the area between part of the third oxide layer and part of the fourth oxide layer. The orthographic projection of the ion-implanted layer onto the substrate does not overlap with the orthographic projection of the area between the third and fourth oxide layers onto the substrate, making region S6 a light-emitting region. This further increases the area of ​​the light-emitting region.

[0098] Optionally, continue to refer to Figure 18 The length of the region between at least one pair of third oxide layers and a portion of the fourth oxide layer within the plane of the substrate is the maximum length of the light-emitting region within the plane of the substrate. This further saves the area used by the second electrode and increases the area of ​​the light-emitting region. Specifically, the length of the S6 region within the plane can be the maximum length of the light-emitting region within the plane of the substrate.

[0099] Optionally, refer to Figure 22 The vertical cavity surface-emitting laser also includes a second electrode connection pad 009, which is connected to the second electrode.

[0100] The second electrode connection pad 009 includes an overlapping portion pad 0091. The orthographic projection of the overlapping portion pad 0091 on the substrate overlaps with the orthographic projection of the ion implantation layer 60 on the substrate, and the orthographic projection of the overlapping portion pad 0091 on the substrate is located within the orthographic projection of the ion implantation layer 60 on the substrate.

[0101] The orthographic projection of the overlapping pad 0091 on the substrate overlaps with the orthographic projection of the oxide layer (51 / 52) corresponding to the discontinuous sub-oxide trench on the substrate, and the orthographic projection of the overlapping pad 0091 on the substrate is located within the orthographic projection of the oxide layer (51 / 52) corresponding to the discontinuous sub-oxide trench on the substrate.

[0102] Specifically, the orthographic projection of the overlapping pad 0091 on the substrate overlaps with the orthographic projection of the ion implantation layer 60 on the substrate, and the orthographic projection of the overlapping pad 0091 on the substrate is located within the orthographic projection of the ion implantation layer 60 on the substrate. That is, the distance L2 between the ion implantation range of the ion implantation layer 60 and the overlapping pad 0091 is greater than or equal to the minimum distance. This minimum distance is within a preset value range, which can ensure that the orthographic projection of the overlapping pad 0091 on the substrate is located within the orthographic projection of the ion implantation layer 60 on the substrate.

[0103] Optionally, the cross-sectional shape of the oxide layer corresponding to the discontinuous sub-oxide trench in the plane where the substrate is located is a symmetrical shape.

[0104] For example, refer to Figure 23 The cross-sectional shape of the oxide layer 50 corresponding to the discontinuous sub-oxide trenches on the plane of the substrate can be a square symmetrical shape, or other symmetrical shapes. The symmetrical cross-sectional shape of the oxide layer corresponding to the discontinuous sub-oxide trenches on the plane of the substrate ensures that the overall shape of the oxide holes formed by the oxide layer 50 is symmetrical, which in turn ensures that the overall shape of the light-emitting units in the laser is symmetrical, improving the regularity of the light-emitting unit arrangement and facilitating laser fabrication.

[0105] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this application can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this application can be achieved, and this is not limited herein.

[0106] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A vertical-cavity surface-emitting laser, characterized in that, include: Multiple light-emitting units, The light-emitting unit is provided with a light-emitting area, and the light-emitting areas of at least some adjacent light-emitting units overlap; The vertical cavity surface-emitting laser includes a substrate; A first electrode, the first electrode being located on a first surface of the substrate; The light-emitting unit includes a stack of a first Bragg reflector, an active layer, and a second Bragg reflector, wherein the first Bragg reflector is located on a second surface of the substrate opposite to the first surface; An ohmic contact layer is located on the surface of the second Bragg mirror away from the active layer; An oxide trench is provided around the light-emitting unit. An oxide layer is provided between the second Bragg reflector and the active layer. The oxide layer forms an oxide hole. The current is limited by the oxide hole formed by the oxide layer and emits light in the active layer, and then exits from the light-emitting area. The second electrode is located at the edge of the light-emitting unit and surrounds the light-emitting area, and is used to define the light-emitting area. The second electrodes of two overlapping light-emitting units in the light-emitting area are either continuously or discontinuously arranged at the overlap. It also includes an ion implantation layer, which is located above the active layer via the second Bragg mirror from the ohmic contact layer. The oxide trench surrounding a light-emitting unit includes multiple discontinuous sub-oxide trenches; the oxide layer also includes at least one pair of third and fourth partial oxide layers, wherein the sub-oxide trenches corresponding to the third and fourth partial oxide layers are adjacent and discontinuous sub-oxide trenches of the same light-emitting unit; the orthographic projection of the ion implantation layer onto the substrate does not overlap with the orthographic projection of the region between the third and fourth partial oxide layers onto the substrate; the region between the third and fourth partial oxide layers is the light-emitting region; the length of the region between at least one pair of third and fourth partial oxide layers in the plane of the substrate is the maximum length of the light-emitting region in the plane of the substrate.

2. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, The second electrodes of two overlapping light-emitting units in the light-emitting area are either continuously or discontinuously arranged at the non-overlapping locations.

3. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, The vertical cavity surface emitter laser also includes a second electrode connection pad, which connects to the second electrodes of at least two light-emitting units.

4. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, The vertical cavity surface emitter laser further includes a passivation layer that covers the oxide trench and the ohmic contact layer, and the passivation layer is provided with a through hole that exposes the middle region of the second electrode.

5. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, In a light-emitting unit, the orthographic projection of the oxide hole onto the substrate is within the orthographic projection of the substrate in the area enclosed by the second electrode.

6. The vertical-cavity surface-emitting laser according to claim 5, characterized in that, The outline of the oxide pores includes arcs and / or straight lines.

7. The vertical-cavity surface-emitting laser according to claim 5, characterized in that, The outline of the light-emitting area includes arcs and / or straight lines.

8. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, At least two light-emitting units share a common oxide trench.

9. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, The oxide layer includes a first oxide layer and a second oxide layer. The sub-oxide trenches corresponding to the first oxide layer and the sub-oxide trenches corresponding to the second oxide layer are adjacent but discontinuous sub-oxide trenches of the same light-emitting unit. The orthogonal projection of the ion implanted layer onto the substrate connects to or covers a portion of the orthogonal projection of the first portion of the oxide layer onto the substrate, and connects to or covers a portion of the orthogonal projection of the second portion of the oxide layer onto the substrate. The current path is confined by the region enclosed by the oxide layer and the ion implantation layer, and light is emitted in the active layer and then emitted from the light-emitting region.

10. The vertical-cavity surface-emitting laser according to claim 9, characterized in that, The vertical cavity surface-emitting laser also includes a second electrode connection pad, which is connected to the second electrode. The second electrode connection pad includes an overlapping portion pad, wherein the orthographic projection of the overlapping portion pad on the substrate overlaps with the orthographic projection of the ion implanted layer on the substrate, and the orthographic projection of the overlapping portion pad on the substrate is located within the orthographic projection of the ion implanted layer on the substrate. The overlapping portion of the pads overlaps with the orthographic projection of the oxide layer corresponding to the discontinuous sub-oxide trench on the substrate, and the orthographic projection of the overlapping portion of the pads on the substrate is located within the orthographic projection of the oxide layer corresponding to the discontinuous sub-oxide trench on the substrate.

11. The vertical-cavity surface-emitting laser according to claim 1, characterized in that, The cross-sectional shape of the oxide layer corresponding to the discontinuous sub-oxide trenches in the plane of the substrate is symmetrical.

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