A VCSEL chip and its preparation method, optical module and its light emitting component

Abstract

The present invention discloses a VCSEL chip and a preparation method thereof, an optical module and an optical emission component thereof. The VCSEL chip includes: a VCSEL device, the VCSEL device includes a substrate, a bottom reflector structure, a resonant cavity structure and a top reflector structure distributed in sequence; and a heating device, the heating device is arranged at the bottom position of the VCSEL device, and the heating device is in contact with the substrate. Since the VCSEL chip includes the VCSEL device and the heating device, the heating device is arranged at the bottom position of the VCSEL device, and the heating device can actively heat the VCSEL device. The heating device located at the bottom can also prevent heat loss and achieve a better thermal insulation effect. When the outside world is in a low temperature environment, the active heating of the heating device can keep the VCSEL device within a suitable temperature range at all times, avoiding the transmission performance of the VCSEL device from decreasing due to the increase of the internal resistance of the VCSEL device at low temperature. That is, the setting of the heating device can enable the VCSEL device to still ensure its transmission performance in a low temperature environment, so as to achieve normal operation in a low temperature environment.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor light emitting components, and in particular to a VCSEL chip and a preparation method thereof, an optical module and a light emitting component thereof. Background Art

[0002] With the continuous development of high-speed optical communication technology, VCSELs (Vertical Cavity Surface Emitting Lasers) are widely used in multimode optical modules. Optical transmitters (OTSs) are components in optical network terminals (ONTs) that convert electrical signals into optical signals. They primarily consist of lasers and the driver circuitry that drives them.

[0003] Optical network terminals are required to operate in temperatures ranging from -40°C to 85°C. However, the internal resistance of VCSELs (Various Laser Electron Lasers) increases with decreasing temperature, placing high demands on the temperature range within which the lasers in these optical transmitters can operate. Currently, addressing the impact of low-temperature environments on VCSEL internal resistance and improving transmission performance in these environments is a pressing technical challenge. Summary of the Invention

[0004] The present invention provides a VCSEL chip and a preparation method thereof, an optical module and a light emitting component thereof, which are used to solve the problem that the VCSEL cannot work normally in a low-temperature environment.

[0005] In one embodiment, a VCSEL chip is provided, including:

[0006] A VCSEL device, the VCSEL device comprising a substrate, a bottom reflector structure, a resonant cavity structure, and a top reflector structure that are sequentially distributed, the resonant cavity structure being used to generate a standing wave; and

[0007] a heating device, the heating device being disposed at the bottom of the VCSEL device, the heating device being in contact with the substrate, and being used to heat the VCSEL device;

[0008] The substrate is provided with a heat preservation structure having a heat preservation cavity, at least part of the heat preservation cavity is located in the area between the heating device and the bottom reflector structure, and the heat preservation structure is used to accommodate the heat generated by the heating device.

[0009] In one embodiment, the heat-insulating structure is an annular groove, a connecting portion is provided in the middle of the annular groove, and the heating device is connected to the connecting portion.

[0010] In one embodiment, the vertical cross-section of the connecting portion is an inverted T-shaped structure, and the connecting portion includes a vertical connecting column and a horizontal connecting plate. The vertical connecting column is located in the middle of the annular groove, and the horizontal connecting plate is located on the outside of the annular groove. The heating device is connected to the horizontal connecting plate.

[0011] In one embodiment, the heat-insulating structure includes one or more heat-insulating grooves, and the heat-insulating grooves are extended along a straight line and / or a curve.

[0012] In one embodiment, the heat preservation structure includes one or more heat preservation cavities, and the heat preservation cavities are located in the substrate.

[0013] In one embodiment, the thermal insulation cavity of the thermal insulation structure is filled with a heat-conducting medium.

[0014] In one embodiment, the heating device is a flat structure having a heating surface, and the heating surface is in contact with the bottom surface of the substrate facing away from the bottom reflector structure.

[0015] In one embodiment, the heating device is a metal heating device or a semiconductor heating device.

[0016] In one embodiment, the resonant cavity structure includes at least one active layer and at least one optoelectronic confinement layer, wherein the optoelectronic confinement layer is disposed adjacent to the active layer, and the optoelectronic confinement layer is configured to define a light emitting region of the VCSEL chip.

[0017] In one embodiment, a groove is provided on the bottom surface of the substrate, and part or all of the heating device is located in the groove.

[0018] In one embodiment, a heat conducting layer is provided between the substrate and the heating device.

[0019] In one embodiment, at least two VCSEL devices are included, the substrates of at least two VCSEL devices are connected into an integrated structure, and each VCSEL device is correspondingly provided with at least one heating device.

[0020] In one embodiment, a method for preparing a VCSEL chip is provided, comprising the following steps:

[0021] forming an epitaxial layer on a substrate by adopting an epitaxial process, wherein the epitaxial layer sequentially comprises a bottom reflector structure, a resonant cavity structure, and a top reflector structure;

[0022] A heating device is fabricated on a side of the substrate facing away from the epitaxial layer.

[0023] In one embodiment, it further includes:

[0024] performing step etching and deep trench etching on the epitaxial layer respectively;

[0025] The epitaxial layer is wet oxidized through the deep trench.

[0026] forming a first electrode structure electrically connected to the bottom reflector structure on the exposed surface of the bottom reflector structure;

[0027] A second electrode structure electrically connected to the top reflector structure is formed on a surface of the top reflector structure.

[0028] In one embodiment, before the step of fabricating a heating device on a side of the substrate facing away from the epitaxial layer, the method further comprises:

[0029] A heat preservation structure having a heat preservation cavity is prepared on a side of the substrate facing away from the epitaxial layer, and at least a portion of the heat preservation cavity is located in a region between the heating device and the bottom reflector structure.

[0030] In one embodiment, the heat preservation cavity is manufactured by performing a dry etching and / or wet etching process on the substrate.

[0031] In one embodiment, a light emitting assembly for an optical module is provided, comprising a driver and at least one VCSEL chip as described above electrically connected to the driver.

[0032] In one embodiment, an optical module and a method for manufacturing the same are provided, including a light emitting component, wherein the light emitting component adopts the above-mentioned light emitting component for the optical module.

[0033] According to the VCSEL chip and its preparation method, optical module and its light emitting component according to the above embodiment, since the VCSEL chip includes a VCSEL device and a heating device, the heating device is arranged at the bottom of the VCSEL device. The heating device can actively heat the VCSEL device. The heating device located at the bottom can also prevent heat loss, achieving a better thermal insulation effect. When the external environment is in a low temperature environment, the active heating of the heating device can keep the VCSEL device within a suitable temperature range, avoiding the transmission performance degradation of the VCSEL device due to the increase of the low-temperature internal resistance. That is, the provision of the heating device can ensure that the VCSEL device can still maintain its transmission performance in a low-temperature environment, thereby achieving normal operation in a low-temperature environment.

[0034] The VCSEL chip of this embodiment can directly integrate a heating device on the original VCSEL device using semiconductor technology, which can reduce the volume and manufacturing cost of the heating device; and can also improve the response speed of the heating device during heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic cross-sectional view of a VCSEL chip in one embodiment;

[0036] Figure 2 A bottom view of a VCSEL chip in one embodiment;

[0037] Figure 3 Schematic cross-sectional view of a VCSEL chip in one embodiment;

[0038] Figure 4 Schematic cross-sectional view of a VCSEL chip in one embodiment;

[0039] Figure 5 Schematic cross-sectional view of a VCSEL chip in one embodiment;

[0040] Figure 6 A bottom view of a VCSEL chip in one embodiment;

[0041] Figure 7 Schematic cross-sectional view of a VCSEL chip in one embodiment;

[0042] Figure 8 Schematic cross-sectional view of a VCSEL chip in one embodiment;

[0043] Figure 9 Flowchart of a method for preparing a VCSEL chip in one embodiment;

[0044] Figure 10 Flowchart of a method for preparing a VCSEL chip in one embodiment.

[0045] The accompanying drawings are numerals as follows:

[0046] 1- VCSEL device, 11- substrate, 111- groove, 112- thermal insulation structure, 1121- thermal insulation cavity, 113- connection part, 114- thermal conductive medium, 12- bottom reflector structure, 13- resonant cavity structure, 131- active layer, 132- photoelectric confinement layer, 14- top reflector structure, 15- first electrode structure, 16- second electrode structure;

[0047] 2- Heating device;

[0048] 3-Thermal conductive layer. DETAILED DESCRIPTION

[0049] The present invention will be further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are numbered with associated similar elements. In the following embodiments, many detailed descriptions are provided to enable the present application to be better understood. However, those skilled in the art will readily appreciate that some of the features may be omitted in different circumstances, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification. This is to avoid the core portion of the present application being overwhelmed by excessive descriptions, and for those skilled in the art, it is not necessary to describe these related operations in detail. They will fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0050] In addition, the features, operations, or characteristics described in the specification may be combined in any appropriate manner to form various embodiments. Furthermore, the steps or actions in the method description may be reordered or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various sequences in the specification and drawings are provided solely for the purpose of clearly describing a particular embodiment and are not intended to be mandatory, unless otherwise specified.

[0051] Component numbers used herein, such as "first" and "second," are used solely to distinguish the components being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings).

[0052] In one embodiment, a VCSEL chip is provided. The VCSEL chip is a key component within the optical emission assembly of an optical module. The VCSEL chip primarily includes a VCSEL device, which is a vertical cavity surface emitting laser (VCSEL) device consisting of a multi-layer PN junction stack. The VCSEL device is used to generate and emit laser light. The VCSEL chip also includes a heater, located at the bottom of the VCSEL device. The heater is an active heating device that actively heats the VCSEL device, maintaining it within a suitable temperature range. This prevents transmission performance degradation caused by increased low-temperature internal resistance in low-temperature environments. This prevents malfunction or failure of the VCSEL device in low-temperature environments, allowing the VCSEL device to operate normally in low-temperature environments. For example, the VCSEL device can operate normally in environments as low as -40 degrees Celsius. The heater can be turned off in relatively high-temperature environments to prevent overheating.

[0053] Please refer to Figure 1 and Figure 2 In this embodiment, the VCSEL chip mainly includes a VCSEL device 1 and a heating device 2. The heating device 2 is arranged at the bottom of the VCSEL device 1. The top of the VCSEL device 1 is used to emit laser light. The heating device 2 is located at the bottom of the VCSEL device 1 and does not affect the laser emission of the VCSEL device 1. The VCSEL device 1 covers the heating device 2, and the VCSEL device 1 can be used for heat preservation to prevent heat loss.

[0054] The VCSEL device 1 primarily comprises a substrate 11, a bottom reflector structure 12, a resonant cavity structure 13, and a top reflector structure 14, arranged sequentially from bottom to top. The resonant cavity structure 13 is formed by limiting the bottom reflector structure 12 and the top reflector structure 14, i.e., the region between the bottom reflector structure 12 and the top reflector structure 14 constitutes the resonant cavity. The resonant cavity is used to generate standing waves, which are waves formed by two coherent waves propagating in opposite directions on the same straight line and superimposed on each other. Specifically, when the two waves are in phase, their amplitudes add together to form antinodes (i.e., crests). When the two waves are in opposite phases, their amplitudes subtract from each other to form nodes (i.e., troughs). Therefore, the crests and troughs of the standing wave are fixed.

[0055] The substrate 11 is located at the bottom of the VCSEL device 1. The material of the substrate 11 is a non-laser transparent material, including but not limited to GaAs, InP, Si, etc. The substrate 11 is used to block the laser generated by the VCSEL device 1 from being emitted from the lower end of the VCSEL device 1. The bottom reflector structure 12 and the top reflector structure 14 may include a film layer with a periodic change in refractive index to achieve efficient reflection or transmission of light within a specific wavelength range. The film layer with a periodic change in refractive index can be composed of semiconductor materials, dielectric materials, metal-dielectric mixed materials, etc. The bottom reflector structure 12 can be an N-type semiconductor layer, and the top reflector structure 14 can be a P-type semiconductor layer. The materials of the N-type semiconductor layer and the P-type semiconductor layer can include but are not limited to GaAs, AlGaAs, etc., which are not limited here. As long as the definition of the resonant cavity can be achieved, it falls within the protection scope of this embodiment.

[0056] In other embodiments, the bottom reflector structure 12 may also be a P-type semiconductor layer, and the top reflector structure 14 may also be an N-type semiconductor layer.

[0057] In this embodiment, the resonant cavity structure 13 may include multiple stacked active layers 131 and at least one photoelectric confinement layer 132. For example, the number of active regions may be 2, 3, or 4, and the number of active layers 131 may be selected based on usage requirements. Multiple active layers 131 may emit light simultaneously, achieving effective superposition of photons and meeting signal transmission requirements.

[0058] The active layer 131 is used to generate stimulated radiation photons, and the emitted photons are continuously reflected in the resonant cavity defined by the bottom reflector structure 12 and the top reflector structure 14, and are continuously enhanced during the reflection process, thereby finally emitting laser light at a specific wavelength and with sufficient energy.

[0059] The number of photoelectric confinement layers 132 is generally no greater than the number of active areas; for example, there may be two or three, with multiple photoelectric confinement layers 132 and multiple active areas arranged alternately above and below. The photoelectric confinement layers 132 are typically oxidized confinement layers, formed by oxidizing a high-aluminum component to form a P-DBR (Distributed Bragg Reflector). The photoelectric confinement layers 132 may also be tunnel junction, air column, or ion implanted confinement layers. The photoelectric confinement layers 132 are used to define the light-emitting region of the VCSEL device 1 and restrict the flow of current, ensuring that current flows only within the region defined by the photoelectric confinement layers 132, thereby reducing energy consumption and increasing current density. The photoelectric confinement layers 132 can also confine the light field within the light-emitting region defined by the photoelectric confinement layers 132, reducing light scattering and diffraction, improving beam quality, and enhancing signal transmission quality.

[0060] In this embodiment, the VCSEL device 1 further includes a first electrode structure 15 and a second electrode structure 16. The first electrode structure 15 can be disposed on the bottom reflector structure 12, and the second electrode structure 16 can be disposed on the top reflector structure 14. When the bottom reflector structure 12 is connected to an N-type semiconductor layer, the first electrode structure 15 is a negative electrode structure; when the top reflector structure 14 is connected to a P-type semiconductor layer, the second electrode structure 16 is a positive electrode structure. Alternatively, when the bottom reflector structure 12 is connected to a P-type semiconductor layer, the first electrode structure 15 is a positive electrode structure; when the top reflector structure 14 is connected to an N-type semiconductor layer, the second electrode structure 16 is a negative electrode structure. The first and second electrode structures 15, 16 are configured to connect to a power supply circuit and to energize the VCSEL device 1 to generate laser light.

[0061] In this embodiment, the heater 2 is disposed at the bottom of the VCSEL device 1, and the VCSEL device 1 covers the heater 2. The heater 2 heats the VCSEL device 1 from the bottom, and the VCSEL device 1 covers the heater 2 to provide a better thermal insulation effect. Of course, the VCSEL device 1 can also cover a portion of the heater 2, so that the heater 2 can heat the VCSEL device 1 from the bottom. The heater 2 is located in the middle of the bottom of the VCSEL device 1, allowing the VCSEL device 1 to more effectively absorb the heat generated by the heater 2 and prevent heat dissipation.

[0062] Specifically, the VCSEL device 1 is cylindrical, and the heater 2 may also be cylindrical. The outer diameter of the heater 2 is smaller than the outer diameter of the VCSEL device 1, and the centerlines of the heater 2 and the heater 2 are aligned and coincident. Of course, the outer diameter of the heater 2 may also be equal to the outer diameter of the VCSEL device 1 to achieve more efficient heating.

[0063] The heating device 2 may include but is not limited to a metal heating device or a semiconductor heating device, etc. For example, the heating device 2 may be a TiN heating device, a W heating device, a Cu heating device, etc.

[0064] The heating device 2 is preferably a flat structure, and the heating device 2 has a relatively large heating surface and a relatively thin thickness. For example, the thickness of the TiN heating device is 100 nm. The heating surface of the heating device 2 can be directly attached to the bottom surface of the substrate 11 facing away from the bottom reflector structure 12. The heating device 2 is in direct contact with the bottom surface of the substrate 11, and the heating device 2 and the substrate 11 can be fixed by bonding or the like. The heat generated by the heating device 2 is directly transferred to the substrate 11 to achieve heating of the VCSEL device 1. The thin thickness of the heating device 2 can reduce the overall height and volume of the VCSEL chip, and can also allow the VCSEL device 1 to completely cover the heating device 2. The heating device 2 is arranged at the bottom of the VCSEL device 1 with a small gap around the heating device 2, which can improve the thermal insulation effect and prevent heat loss.

[0065] Please refer to Figure 3 In other embodiments, a heat-conducting layer 3 may be provided between the heating device 2 and the substrate 11. The heat-conducting layer 3 can assist the heating device 2 in transferring heat to the substrate 11. The heat-conducting layer 3 may also be a unidirectional heat-conducting structure composed of materials such as carbon / carbon composite. This unidirectional heat-conducting structure can transfer heat from the heating device 2 to the substrate 11 and prevent heat from the substrate 11 from being transferred to the heating device 2, thereby achieving a better heating effect.

[0066] In other embodiments, the top and sides of the VCSEL device 1 may be covered with an insulation layer, which may be an insulation structure such as an insulation film. The insulation layer may effectively prevent the heat generated by the heating device 2 from being lost, thereby providing a heating and insulation effect for the VCSEL chip.

[0067] In this embodiment, since the VCSEL chip includes a VCSEL device 1 and a heater 2, the heater 2 is disposed at the bottom of the VCSEL device 1. The heater 2 can actively heat the VCSEL device 1. The heater 2 located at the bottom can also prevent heat loss, thereby achieving a better thermal insulation effect. When the external environment is in a low-temperature environment, the active heating of the heater 2 can keep the VCSEL device 1 within a suitable temperature range, preventing the transmission performance of the VCSEL device 1 from decreasing due to an increase in the internal resistance of the VCSEL device 1 at low temperatures. In other words, the provision of the heater 2 can ensure that the VCSEL device 1 can still maintain its transmission performance in a low-temperature environment, thereby achieving normal operation in a low-temperature environment.

[0068] The VCSEL chip of this embodiment can directly integrate the heating device 2 on the original VCSEL device 1 using semiconductor technology, which can reduce the volume and manufacturing cost of the heating device 2; and can improve the response speed of the heating device 2 during heating.

[0069] Please refer to Figure 4 In one embodiment, the bottom surface of the substrate 11 of the VCSEL device 1 may be provided with a groove 111, with the heater 2 partially located within the groove 111. This arrangement increases the contact area between the heater 2 and the substrate 11, improving heating efficiency. Furthermore, the substrate 11 wraps around the heater 2, effectively reducing heat loss from the heater 2.

[0070] In one embodiment, the heating device 2 may also be completely embedded in the groove 111 of the substrate 11, thereby maximizing the contact area between the heating device 2 and the substrate 11 and further reducing heat loss.

[0071] In one embodiment, a plurality of heating devices 2 are provided on the bottom surface of the substrate 11 of the VCSEL device 1, and the plurality of heating devices 2 are evenly distributed on the bottom surface of the substrate 11. This arrangement allows the bottom surface of the substrate 11 to be covered with more heating devices 2, thereby increasing the contact area between the heating devices 2 and the substrate 11, effectively improving the heating efficiency, and achieving a more uniform heating effect.

[0072] Please refer to Figure 5 and Figure 6 In one embodiment, the substrate 11 is provided with a thermal insulation structure 112, which has a thermal insulation cavity 1121. At least a portion of the thermal insulation cavity 1121 of the thermal insulation structure 112 is located in the area between the heater 2 and the bottom reflector structure 12. The thermal insulation cavity 1121 of the thermal insulation structure 112 can be filled with air. Air has low thermal conductivity and can concentrate heat below the VCSEL device 1. That is, the thermal insulation structure 112 can be used to accommodate the heat generated by the heater 2, reduce heat dissipation, and improve heating efficiency and insulation time in low-temperature environments.

[0073] The insulation structure 112 can be a trough structure with an opening provided on the bottom surface of the substrate 11. The opening is connected to the insulation cavity 1121 of the insulation structure 112. This arrangement facilitates the processing of the insulation structure 112 while allowing air to enter the insulation cavity 1121 of the insulation structure 112. The trough-shaped insulation structure 112 can be manufactured using dry etching or wet etching.

[0074] The heat preservation structure 112 is preferably an annular groove, and a connecting portion 113 is provided in the middle of the annular groove, and the heating device 2 is connected to the connecting portion 113. In this way, the heat preservation structure 112 can be distributed around the heating device 2, which can improve the heat preservation effect.

[0075] Specifically, the vertical cross-section of the connecting portion 113 can have an inverted T-shaped structure. Connecting portion 113 includes a vertical connecting post and a horizontal connecting plate. The vertical connecting post is located in the middle of the annular groove, while the horizontal connecting plate is located outside the annular groove. That is, the vertical connecting post is arranged along the direction of laser emission from the VCSEL device 1, while the horizontal connecting plate is perpendicular to the direction of laser emission from the VCSEL device 1. The heating device 2 is connected to the horizontal connecting plate. Arranging connecting portion 113 in an inverted T-shaped structure ensures sufficient contact area between the heating device 2 and the substrate 11. It also allows the majority of the insulation cavity 1121 of the insulation structure 112 to extend above the heating device 2, significantly improving heating efficiency and insulation time in low-temperature environments.

[0076] In one embodiment, the heat preservation structure 112 may also be other structures, for example, the heat preservation structure 112 includes one or more linear heat preservation grooves, and the linear heat preservation grooves are arranged along straight lines and / or curves. The linear heat preservation grooves also have a heat preservation cavity 1121, which can achieve a heat preservation effect.

[0077] In one embodiment, the insulation structure 112 may also be an insulation cavity, which is located in the substrate 11 and has a closed insulation cavity body 1121 , and may also improve the heating efficiency and insulation time in a low-temperature environment.

[0078] Please refer to Figure 7 In one embodiment, the insulation cavity 1121 of the insulation structure 112 is filled with a heat-conducting medium 114. The heat-conducting medium 114 can be a material with high thermal conductivity, such as a solidified material filled with metal powder. The heat-conducting medium 114 can improve the heating efficiency in a low-temperature environment. At the same time, the heat-conducting medium 114 is different from the material of the substrate 11, forming a multi-layer insulation effect, which can increase the insulation time.

[0079] Please refer to Figure 8In one embodiment, the VCSEL chip includes at least two VCSEL devices 1, and the at least two VCSEL devices 1 are connected into an integrated structure, wherein the substrates 11 of the at least two VCSEL devices 1 are an integrated structure, and the bottom reflector structures 12 of the at least two VCSEL devices 1 can also be an integrated structure.

[0080] At least two VCSEL devices 1 can be distributed in an array, for example, forming a 4×4 array. Each VCSEL device 1 is provided with at least one heater 2, for example, one heater 2 is provided for each VCSEL device 1, so that each VCSEL device 1 has an independent heater 2 for heating and insulation, ensuring that all VCSEL devices 1 on the VCSEL chip can operate normally in a low-temperature environment.

[0081] In one embodiment, a light emitting assembly for an optical module is provided. The light emitting assembly includes a driver and at least one VCSEL chip according to any of the above embodiments. The driver is connected to the VCSEL chip and is used to drive the VCSEL device 1 on the VCSEL chip to generate and emit laser light. The light emitting assembly is part of the optical module and is used to convert electrical signals into optical signals, enabling data transmission via light.

[0082] In the optical transmission component used in the optical module of this embodiment, since the VCSEL chip is provided with the heating device 2 , the optical transmission component can maintain good transmission performance in a low temperature environment, thereby ensuring the quality of optical communication.

[0083] In one embodiment, an optical module is provided. The optical module of this embodiment includes the above-mentioned light emitting component for the optical module. The optical module transmits an optical signal through the light emitting component to transmit a signal.

[0084] Since the VCSEL chip is provided with a heating device 2 , the optical module can maintain good transmission performance in a low temperature environment, thereby ensuring the quality of optical communication.

[0085] In one embodiment, a method for preparing a VCSEL device is provided. The method is used to prepare the above-mentioned VCSEL chip. The VCSEL chip includes a VCSEL device 1 and a heating device 2. The VCSEL device 1 includes a substrate 11, a bottom reflector structure 12, a resonant cavity structure 13, and a top reflector structure 14.

[0086] Please refer to Figure 9 The method for preparing the VCSEL device in this embodiment mainly includes the following steps:

[0087] S10: forming an epitaxial layer on the substrate using an epitaxial process, wherein the epitaxial layer sequentially includes a bottom reflector structure, a resonant cavity structure, and a top reflector structure;

[0088] In this embodiment, a bottom reflector structure, a resonant cavity structure 13, and a top reflector structure are sequentially formed on a substrate using an epitaxial process to produce a VCSEL device 1. The epitaxial process may include, but is not limited to, metal organic chemical vapor deposition (MOCVD), molecular layer epitaxy (MLE), or atomic layer deposition (ALD). A wafer having a multi-layer VCSEL structure is obtained, thereby producing the VCSEL device 1.

[0089] The bottom reflector structure 12 , the resonant cavity structure 13 and the top reflector structure 14 are formed one by one on the substrate through an epitaxial process.

[0090] S20: fabricating a heating device on a side of the substrate facing away from the epitaxial layer;

[0091] In this method, a deposition process is used to manufacture the heating device 2 on the side of the substrate 11 facing away from the epitaxial layer. The heating device 2 is manufactured based on the VCSEL device 1, and the heating device 2 and the VCSEL device 1 form an integrated structure.

[0092] Specifically, a deposition process is used to form the heating device 2 on the bottom surface (the side facing away from the epitaxial layer) of the substrate 11 of the VCSEL device 1, wherein the heating device 2 can be a heating layer, and the deposition process includes but is not limited to at least one of sputtering, ion plating, chemical plating, chemical vapor deposition, thermal spraying, evaporation and electroplating.

[0093] Preferably, the VCSEL device 1 is prepared as a cylindrical structure, and the heating device 2 is also prepared as a cylindrical structure. The heating device 2 is located in the middle of the bottom of the VCSEL device 1. The outer diameter of the heating device 2 is smaller than the outer diameter of the substrate 11 of the VCSEL device 1, or the outer diameter of the heating device 2 can also be equal to the outer diameter of the substrate 11 of the VCSEL device 1.

[0094] The thickness and width (diameter) of the heater 2 affect its sheet resistance. For example, when the thickness of the heater 2 is approximately 100 nm, a thickness variation of ±5 nm will cause a sheet resistance variation of ±0.75 Ω. Therefore, the thickness and width of the heater 2 should be set to a reasonable size based on the heating requirements, so that the heater 2 can meet the heating requirements while maintaining a minimal footprint.

[0095] S30: performing step etching and deep trench etching on the epitaxial layer respectively;

[0096] The epitaxial layer is subjected to step etching and deep trench etching to form steps and grooves in the epitaxial layer to obtain a plurality of epitaxial structures. Each epitaxial structure is separated by a groove, and the groove exposes a portion of the surface of the bottom reflector structure 12 .

[0097] S40: wet oxidation of the epitaxial layer through the deep trench;

[0098] The sidewalls of each epitaxial layer are oxidized by a wet oxidation process, so that a portion of the top reflector structure 14 is oxidized to form a photoelectric confinement layer.

[0099] S50: forming a first electrode structure electrically connected to the bottom reflector structure on the exposed surface of the bottom reflector structure;

[0100] In this step: a passivation layer is first formed on the surface of the exposed bottom reflector structure 12 using a deposition process; a through hole is made in the passivation layer, exposing the surface of the bottom reflector structure 12; a first electrode structure 15 is formed based on the through hole, and the first electrode structure 15 is electrically connected to the bottom reflector structure 12; wherein, the first electrode structure 15 may include two first electrode structures 15 for electrically connecting to adjacent VCSEL devices 1.

[0101] S60: forming a second electrode structure electrically connected to the top reflector structure on a surface of the top reflector structure.

[0102] A second electrode structure 16 is formed on the surface of the top reflector structure by a deposition process. The second electrode structure 16 is electrically connected to the top reflector structure 14. The second electrode structure 16 may include two for electrically connecting to adjacent VCSEL devices 1.

[0103] Among them, steps S30-S60 can be performed before or after step S20, and the production order can be selected according to needs.

[0104] In the VCSEL device fabricated by this method, the heater 2 is located at the bottom of the VCSEL device 1. The heater 2 can actively heat the VCSEL device 1. The bottom heater 2 also prevents heat loss, providing better insulation. When the external environment is in a low-temperature environment, the active heating of the heater 2 can keep the VCSEL device 1 within a suitable temperature range, preventing the transmission performance of the VCSEL device 1 from decreasing due to the increase in the low-temperature internal resistance. In other words, the installation of the heater 2 can ensure that the VCSEL device 1 can maintain its transmission performance in low-temperature environments, thereby achieving normal operation in low-temperature environments.

[0105] The VCSEL chip of this embodiment can directly integrate the heating device 2 on the original VCSEL device 1 using semiconductor technology, which can reduce the volume and manufacturing cost of the heating device 2; and can improve the response speed of the heating device 2 during heating.

[0106] In one embodiment, a method for preparing a VCSEL device is provided, which further includes the following steps before step S20:

[0107] S15, preparing a heat preservation structure having a heat preservation cavity on a side of the substrate facing away from the epitaxial layer, wherein at least a portion of the heat preservation cavity is located in a region between the heating device and the bottom reflector structure.

[0108] In this step, a heat-insulating structure 112 is formed on the bottom of the substrate 11 (on the side away from the epitaxial layer) by dry etching and / or wet etching. At least part of the heat-insulating structure 112 is located in the area between the heating device 2 and the bottom reflector structure 12.

[0109] The prepared thermal insulation structure 112 is preferably an annular groove. The thermal insulation structure 112 has a thermal insulation cavity 1121. The thermal insulation cavity 1121 can be filled with air or a heat-conducting medium, which can effectively improve the thermal insulation effect.

[0110] An inverted T-shaped connecting portion 113 is formed in the middle of the insulation structure 112. This portion includes a vertical connecting post and a horizontal connecting plate. The vertical connecting post is located in the middle of the annular groove, while the horizontal connecting plate is located outside the annular groove. In other words, the vertical connecting post is positioned along the direction of laser emission from the VCSEL device 1, while the horizontal connecting plate is perpendicular to the direction of laser emission from the VCSEL device 1. The formation of connecting portion 113 allows the heater to be positioned in the middle of the bottom of the VCSEL device 1.

[0111] In this embodiment, in step S20, a heating device 2 is fabricated on the transverse connecting plate of the connecting portion 113 at the bottom of the substrate 11 using a deposition process. The diameter of the heating device 2 can be equal to or smaller than the diameter of the transverse connecting plate of the connecting portion 113. The deposition process includes, but is not limited to, at least one of sputtering, ion plating, electroless plating, chemical vapor deposition, thermal spraying, evaporation, and electroplating. Preferably, the diameter of the heating device 2 is equal to the diameter of the transverse connecting plate of the connecting portion 113, fully expanding the area of the heating device 2 to achieve a better heating effect.

[0112] In the VCSEL device prepared by this method, the heating device 2 is located at the bottom of the VCSEL device 1. The heating device 2 can actively heat the VCSEL device 1. The heating device 2 located at the bottom can also prevent heat loss, achieving a better thermal insulation effect. When the external environment is in a low-temperature environment, the active heating of the heating device 2 can keep the VCSEL device 1 within a suitable temperature range, preventing the transmission performance of the VCSEL device 1 from decreasing due to the increase in the low-temperature internal resistance. In other words, the provision of the heating device 2 can ensure that the VCSEL device 1 can still maintain its transmission performance in a low-temperature environment, thereby achieving normal operation in a low-temperature environment.

[0113] Furthermore, the heat-insulating structure 112 of the substrate 11 can be used to accommodate the heat generated by the heating device 2, thereby reducing heat dissipation and improving the heating efficiency and heat-insulating time in a low-temperature environment.

[0114] The above examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. Those skilled in the art can make several simple deductions, modifications or substitutions based on the concept of the present invention.

Claims

1. A VCSEL chip for optical communication, characterized in that: include: A VCSEL device, the VCSEL device comprising a substrate, a bottom reflector structure, a resonant cavity structure and a top reflector structure distributed in sequence, the resonant cavity structure being used to generate a standing wave; as well as a heating device, the heating device being disposed at the bottom of the VCSEL device, the heating device being in contact with the substrate, and being used to heat the VCSEL device; In which, the substrate is provided with an insulation structure having an insulation cavity, at least part of the insulation cavity is located in the area between the heating device and the bottom reflector structure, and the insulation structure is used to accommodate the heat generated by the heating device; the bottom surface of the substrate is provided with an opening, and the opening is connected to the insulation cavity.

2. The VCSEL chip for optical communication according to claim 1, wherein: The heat-insulating structure is an annular groove, a connecting portion is provided in the middle of the annular groove, and the heating device is connected to the connecting portion.

3. The VCSEL chip for optical communication according to claim 2, wherein: The vertical cross-section of the connecting portion is an inverted T-shaped structure, and the connecting portion includes a vertical connecting column and a horizontal connecting plate. The vertical connecting column is located in the middle of the annular groove, and the horizontal connecting plate is located on the outside of the annular groove. The heating device is connected to the horizontal connecting plate.

4. The VCSEL chip for optical communication according to claim 1, wherein: The heat-insulating structure includes one or more heat-insulating grooves, and the heat-insulating grooves are extended along a straight line and / or a curve.

5. The VCSEL chip for optical communication according to claim 1, wherein: The heat preservation structure includes one or more heat preservation cavities, and the heat preservation cavities are located in the substrate.

6. The VCSEL chip for optical communication according to claim 1, wherein: The heat-insulating cavity of the heat-insulating structure is filled with a heat-conducting medium.

7. The VCSEL chip for optical communication according to claim 1, wherein: The heating device is a flat structure and has a heating surface. The heating surface is in contact with the bottom surface of the substrate facing away from the bottom reflector structure.

8. The VCSEL chip for optical communication according to claim 7, wherein: The heating device is a metal heating device or a semiconductor heating device.

9. The VCSEL chip for optical communication according to claim 1, wherein: The resonant cavity structure includes at least one active layer and at least one optoelectronic confinement layer. The optoelectronic confinement layer is disposed adjacent to the active layer and is configured to define a light emitting region of the VCSEL chip.

10. The VCSEL chip for optical communication according to claim 1, wherein: A groove is provided on the bottom surface of the substrate, and part or all of the heating device is located in the groove.

11. The VCSEL chip for optical communication according to any one of claims 1 to 10, characterized in that: It comprises at least two VCSEL devices, the substrates of the at least two VCSEL devices are connected into an integrated structure, and each VCSEL device is correspondingly provided with at least one heating device.

12. A method for preparing a VCSEL chip for optical communication, characterized in that: The steps include: forming an epitaxial layer on a substrate using an epitaxial process, wherein the epitaxial layer sequentially comprises a bottom reflector structure, a resonant cavity structure, and a top reflector structure; A heat preservation structure having a heat preservation cavity is prepared on a side of the substrate facing away from the epitaxial layer; an opening is provided on the bottom surface of the substrate, and the opening is connected to the heat preservation cavity; A heating device is fabricated on a side of the substrate facing away from the epitaxial layer, and at least a portion of the heat preservation cavity is located in a region between the heating device and the bottom reflector structure.

13. The method for preparing a VCSEL chip for optical communication according to claim 12, wherein: Also includes: performing step etching and deep trench etching on the epitaxial layer respectively; performing wet oxidation on the epitaxial layer through the deep trench; forming a first electrode structure electrically connected to the bottom reflector structure on the exposed surface of the bottom reflector structure; A second electrode structure electrically connected to the top reflector structure is formed on a surface of the top reflector structure.

14. The method for preparing a VCSEL chip for optical communication according to claim 12, wherein: The heat preservation cavity is manufactured by performing a dry etching and / or wet etching process on the substrate.

15. An optical transmission component for optical communication, characterized in that: The method comprises a driver and at least one VCSEL chip for optical communication according to any one of claims 1 to 11 electrically connected to the driver.

16. An optical module for optical communication, characterized in that: It comprises a light emitting component and a light receiving component, wherein the light emitting component adopts the light emitting component for optical communication as claimed in claim 15.

Images