Molecular beam epitaxy equipment and vertical cavity surface laser growth method

Abstract

The invention belongs to the field of molecular beam epitaxy equipment, and discloses molecular beam epitaxy equipment and a vertical cavity surface laser growth method. A formal product and a test structure are grown on the same tray at the same time, and the growth of the test structure is controlled by using a shielding device; the problem that in the prior art, a test structure needs to be independently grown or formal products need to be complexly processed is solved, and the method has the advantages of saving time and source materials, improving growth parameter control precision and facilitating problem positioning.

Description

Technical Field

[0001] The present application relates to the field of molecular beam epitaxy equipment, and in particular, to a molecular beam epitaxy equipment and a vertical cavity surface laser growth method. Background Art

[0002] Vertical Cavity Surface Emitting Laser (VCSEL) is a semiconductor laser that emits light perpendicular to the surface of the semiconductor substrate. Compared with traditional edge-emitting lasers, VCSEL has many advantages, including low manufacturing cost, low threshold, low power consumption, good beam quality, small divergence angle, easy device coupling, high-speed modulation, and array integration. These advantages have made VCSEL receive widespread attention and attention in recent years.

[0003] The structure of VCSEL is mainly composed of multi-layer distributed Bragg reflectors (DBR) located on the upper and lower sides and multi-layer quantum well / point active regions located between the two DBR structures. Compared with most other microelectronic and optoelectronic devices, this complex structure makes the growth control and post-growth structure testing of VCSEL more challenging.

[0004] Specifically, the thick DBR structure on the active region of the VCSEL structure makes it difficult to directly measure the photoluminescence (PL) spectrum of the active region. At the same time, the thick DBR structure on the upper and lower sides will produce a large number of peaks in the X-ray diffraction (XRD) measurement, which makes it difficult to accurately fit the thickness and composition.

[0005] In order to ensure the repeatability and stability of growth, existing growth technologies usually require the use of test structures to adjust and calibrate growth parameters at intervals. The general practice is to insert a separate test structure growth after completing several rounds of complete VCSEL formal structure growth. This test structure usually only includes the lower DBR structure and the active area. The test structure is used for structural testing, and the test results are used to adjust and calibrate growth parameters.

[0006] However, this method has some obvious drawbacks. First, in production-type molecular beam epitaxy equipment, no matter how many wafers are placed on a substrate holder for growth, the same source furnace material will be consumed. Therefore, if a round of growth that only grows test structures is inserted in the middle, it will cause a waste of time and source materials. Secondly, because the growth conditions between different growth rounds are slightly different, the test results of a single growth round cannot accurately reflect the equipment status when other rounds of formal structures are growing, especially for growth parameters that need to be precisely controlled. In addition, if there is a problem with the test structure, it is difficult to determine which round of the previous formal structures has the problem.

[0007] Another existing technology is to take samples from the grown formal structure, remove the upper DBR structure through specific treatment methods such as corrosion, and then test after exposing the active area. However, the processing process of this method is relatively cumbersome and time-consuming, and a slight deviation will lead to inaccurate test results. Therefore, this method is not only time-consuming, but also has extremely high requirements for the processing personnel and the processing process.

[0008] In view of the above problems, the existing technology needs to be improved urgently. Summary of the invention

[0009] The purpose of the present application is to provide a molecular beam epitaxy device and a vertical cavity surface laser growth method, which have the advantages of saving time and source materials, improving the control accuracy of growth parameters, and facilitating problem location.

[0010] In a first aspect, the present application provides a molecular beam epitaxy device, comprising a growth chamber, and further comprising: A tray, comprising a product area and a test area, wherein the product area is provided with at least one first positioning groove, the first positioning groove is used to position and place a first substrate, the first substrate is used to grow a formal product, and the test area is provided with at least one second positioning groove, the second positioning groove is used to position and place a second substrate, the second substrate is used to grow a test structure; the test structure is the same as a part of the growth structure of the formal product; A heater, disposed on the lower side of the tray and used for heating the tray; The shielding device can shield and open the second positioning groove, and is used to shield the second positioning groove in time during the growth process, so that the test structure is formed on the second substrate in the second positioning groove.

[0011] By growing the formal product and the test structure on the same tray at the same time and using a shielding device to control the growth of the test structure, the problem of needing to grow the test structure separately or complicatedly process the formal product in the prior art is solved. This has the advantages of saving time and source materials, improving the accuracy of growth parameter control, and facilitating problem location.

[0012] Preferably, the product area is a circular area located in the middle of the tray, and the test area is an annular area surrounding the product area.

[0013] By setting the product area in the central circular area, it is possible to ensure that the formal product substrate is in the best position in the growth chamber and obtain uniform growth conditions. At the same time, setting the test area as a ring area surrounding the product area does not affect the growth of formal products, and can also grow test structures in the same batch. This layout achieves the synchronous growth of formal products and test structures, improves production efficiency, and saves time and material costs.

[0014] Preferably, the heater comprises a first heating zone for heating the product zone and a second heating zone for heating the test zone; the heating powers of the first heating zone and the second heating zone can be adjusted independently.

[0015] By independently adjusting the power of these two heating zones, the temperature uniformity of the tray can be better guaranteed, thereby improving the consistency of growth conditions for each substrate.

[0016] Preferably, the first heating zone comprises a main heating zone located in the middle and an annular transition heating zone surrounding the main heating zone, and the heating powers of the main heating zone and the annular transition heating zone can be adjusted independently.

[0017] Preferably, an isolation groove is provided between the product area and the test area.

[0018] Preferably, a heat shielding ring is provided between the first heating zone and the second heating zone, and the heat shielding ring passes through the isolation groove.

[0019] Preferably, the heat shielding ring comprises an inner ring layer and an outer ring layer, and a gap is provided between the inner ring layer and the outer ring layer.

[0020] Preferably, the shielding device comprises at least one shielding unit, each of the shielding units comprises a shielding piece and a driving mechanism, and the driving mechanism is used to drive the shielding piece to cover or move away from the test area, thereby shielding or opening the second positioning groove.

[0021] Preferably, a plurality of the shielding units are provided, and the shielding pieces are arc-shaped shielding pieces, and when all the shielding pieces cover the test area, the test area can be completely covered.

[0022] In a second aspect, the present application provides a method for growing a vertical cavity surface laser. Based on the molecular beam epitaxy device described above, the method for growing a vertical cavity surface laser comprises the following steps: A1. Place a first substrate in a first positioning groove of a tray, and place a second substrate in at least one of the second positioning grooves; A2. Heating the tray to a growth temperature; A3. When the shielding device opens the second positioning groove, the lower DBR structure and the active area are sequentially grown on the first substrate and the second substrate to form a test structure on the second substrate; A4. Closing the second positioning groove by the shielding device and continuing to grow the upper DBR structure on the first substrate to form a formal product on the first substrate; A5. After cooling down, take out the formal product and the test structure; A6. Perform structural testing on the test structure and adjust growth parameters for the next round of growth based on the test results.

[0023] Beneficial effects: The molecular beam epitaxy equipment and vertical cavity surface laser growth method provided in the present application solve the problem of needing to grow the test structure separately or to process the formal product in a complicated manner in the prior art by simultaneously growing the formal product and the test structure on the same tray and using a shielding device to control the growth of the test structure. The method has the advantages of saving time and source materials, improving the accuracy of growth parameter control, and facilitating problem location. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A top view of the tray.

[0025] Figure 2 A top view of the heater.

[0026] Figure 3 A side view of the tray and heater.

[0027] Figure 4 A top view of the occluding unit.

[0028] Figure 5 A side view of the occlusion unit.

[0029] Figure 6 The figure is a flow chart of a method for growing a vertical cavity surface laser.

[0030] Explanation of reference numerals: 1. tray; 101. product area; 102. test area; 103. first positioning groove; 104. second positioning groove; 105. isolation groove; 2. heater; 201. first heating zone; 202. second heating zone; 203. main heating zone; 204. annular transition heating zone; 205. heat shielding ring; 206. annular mounting groove; 3. shielding unit; 301. shielding sheet; 3011. overlapping part; 302. driving mechanism; 3021. connecting rod; 3022. driving device; 3023. magnetic sleeve; 4. temperature sensor. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0032] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0033] Vertical Cavity Surface Mount Laser (VCSEL) is an important semiconductor laser, whose structure includes distributed Bragg reflectors (DBR) on the upper and lower sides and a multi-layer quantum well / point active region in the middle. Due to the complexity of the VCSEL structure, its growth control and structural testing face unique challenges. In the prior art, in order to ensure the repeatability and stability of growth, it is necessary to grow and test the test structure regularly to adjust and calibrate the growth parameters. However, this method has some problems.

[0034] Specifically, in molecular beam epitaxy equipment, no matter how many wafers are placed for growth, the same source furnace material will be consumed. If a test structure is grown alone, it will cause a waste of time and materials. In addition, because the conditions between different growth rounds are slightly different, the individually grown test structure cannot accurately reflect the equipment status when the formal structure is grown. This makes it difficult to accurately adjust the growth parameters, affecting the production efficiency and quality control of VCSELs.

[0035] To do this, please refer to Figure 1-Figure 5 The present application provides a molecular beam epitaxy device, comprising a growth chamber, and further comprising: A tray 1, comprising a product area 101 and a test area 102, wherein the product area 101 is provided with at least one first positioning groove 103, the first positioning groove 103 is used to position and place a first substrate, and the first substrate is used to grow a formal product (such as a VCSEL product), and the test area 102 is provided with at least one second positioning groove 104, the second positioning groove 104 is used to position and place a second substrate, and the second substrate is used to grow a test structure; the test structure is the same as part of the growth structure of the formal product (for example, the test structure only includes the lower DBR structure and the active area of ​​the VCSEL product); A heater 2 is disposed on the lower side of the tray 1 and is used to heat the tray 1; The shielding device can shield and open the second positioning groove 104 and is used to shield the second positioning groove 104 in a timely manner during the growth process so that a test structure is formed on the second substrate in the second positioning groove 104 .

[0036] By growing the formal product and the test structure on the same tray 1 at the same time and using a shielding device to control the growth of the test structure, the problem of needing to grow the test structure separately or to process the formal product in a complicated manner in the prior art is solved. This has the advantages of saving time and source materials, improving the accuracy of growth parameter control, and facilitating problem location.

[0037] The tray 1 refers to a platform structure for placing a substrate, and can be implemented in the shape of a disk made of metal material or graphite or other materials.

[0038] The first positioning groove 103 and the second positioning groove 104 refer to groove structures for fixing the substrate on the tray 1, which can be implemented by using circular or square grooves matching the shape of the substrate. The size of the second positioning groove 104 can be smaller than or equal to the size of the first positioning groove 103, preferably smaller than the size of the first positioning groove 103, which will not affect the growth of each layer of the test structure, thereby not affecting the test results, and can save materials.

[0039] The heater 2 refers to a device for heating the tray 1 , and can be implemented by a resistance heating element or a radiation heating element.

[0040] The shielding device refers to a mechanism for controlling the exposure state of the second positioning groove 104 , and can be specifically implemented by a movable shielding sheet 301 and a driving mechanism 302 .

[0041] Specifically, by setting the product area 101 and the test area 102 on the same tray 1 and using a shielding device, the purpose of growing the formal product and the test structure simultaneously in a single growth process is achieved. This design not only improves equipment utilization and reduces material waste, but also ensures that the test structure and the formal product grow under the same conditions, thereby improving the accuracy and representativeness of the test results. The specific use process is, for example: First, when growing the lower DBR structure and the active area, the second positioning groove 104 remains open, so that the first substrate and the second substrate receive the molecular beam at the same time. After the lower DBR structure and the active area are grown, the shielding device moves to the shielding position to cover the second positioning groove 104. In this way, the growth process on the second substrate is interrupted to form a test structure, while the first substrate continues to grow a complete VCSEL structure. Finally, the test structure can be taken out for structural testing.

[0042] The shapes and arrangements of the product area 101 and the test area 102 can be set according to actual needs.

[0043] In some possible implementations, see Figure 1 The product area 101 is a circular area located in the middle of the tray 1 , and the test area 102 is an annular area surrounding the product area 101 .

[0044] By setting the product area 101 as the central circular area, it is possible to ensure that the formal product substrate (i.e., the first substrate) is in the best position in the growth chamber and obtain uniform growth conditions. At the same time, setting the test area 102 as a ring area surrounding the product area 101 does not affect the growth of the formal product, and can simultaneously grow the test structure in the same batch. This layout achieves the synchronous growth of the formal product and the test structure, improves production efficiency, and saves time and material costs.

[0045] In addition, the design of the annular test area 102 can also place multiple test substrates (i.e., second substrates) at different positions, and the test results of test structures at multiple different positions can be integrated to adjust the growth parameters, which is beneficial to improving the accuracy of the test results, thereby improving the accuracy and scientificity of the growth parameter adjustment.

[0046] In some preferred embodiments, see Figure 2 , Figure 3 The heater 2 includes a first heating zone 201 for heating the product zone 101 and a second heating zone 202 for heating the test zone 102; the heating powers of the first heating zone 201 and the second heating zone 202 can be adjusted independently.

[0047] The first heating zone 201 is mainly responsible for heating the circular product zone 101 in the middle of the tray 1 to ensure the growth temperature of the formal product. The second heating zone 202 is responsible for heating the annular test zone 102 surrounding the product zone 101 to control the growth temperature of the test structure. By independently adjusting the power of the two heating zones, the temperature uniformity of the tray 1 can be better guaranteed, thereby improving the consistency of the growth conditions of each substrate.

[0048] Further, see Figure 2 The first heating zone 201 may include a main heating zone 203 located in the middle and an annular transition heating zone 204 surrounding the main heating zone 203 , and the heating powers of the main heating zone 203 and the annular transition heating zone 204 can be adjusted independently.

[0049] This design can more finely control the temperature distribution of the product area 101 and improve the heating uniformity. Specifically, the main heating zone 203 is mainly responsible for heating the central part of the product area 101, while the annular transition heating zone 204 is responsible for heating the edge of the product area 101. Since there may be heat loss at the edge of the product area 101, the setting of the annular transition heating zone 204 can effectively compensate for this heat loss and ensure the uniformity of the overall temperature of the product area 101. In addition, when the test structure is completed, the heating of the test area 102 can be stopped or the heating power of the test area 102 can be reduced. At this time, the heating power of the annular transition heating zone 204 can be appropriately increased to ensure the uniformity of the overall temperature of the product area 101.

[0050] In order to more accurately control the temperature of each heating zone, a temperature sensor 4 (such as Figure 2 As shown), according to the measurement results of the temperature sensor 4, the heating power of each heating zone is dynamically adjusted to better ensure temperature uniformity and ensure that the actual heating curve fits the required heating curve.

[0051] In some possible implementations, see Figure 1 An isolation groove 105 is provided between the product area 101 and the test area 102 .

[0052] By providing the isolation groove 105, the thermal isolation between the product area 101 and the test area 102 can be achieved, which helps to ensure the temperature independence of the two areas. The temperature interference between the product area 101 and the test area 102 is reduced, and the temperature of the two areas can be controlled more accurately and stably, so as to better ensure the consistency of the temperature conditions of the substrates in the two areas.

[0053] The isolation groove 105 can be arranged in a variety of ways. For example, an annular groove can be directly processed on the tray 1, and the groove is located between the product area 101 and the test area 102. The depth and width of the groove can be adjusted according to actual needs (for example, the width can be 1.5 cm) to achieve the best thermal isolation effect. Another possible implementation method is to use a material with low thermal conductivity to fill between the product area 101 and the test area 102 to form an insulation layer.

[0054] Further, see Figure 2 , Figure 3 A heat shielding ring 205 may be disposed between the first heating zone 201 and the second heating zone 202 , and the heat shielding ring 205 passes through the isolation groove 105 (thereby, the isolation groove 105 has a downward opening, and the upper portion of the heat shielding ring 205 extends into the isolation groove 105 from the opening).

[0055] The setting of the heat shielding ring 205 can reduce the heating interference between the first heating zone 201 and the second heating zone 202 on the one hand, and can further reduce the heat transfer between the product zone 101 and the test zone 102 on the other hand, thereby further improving the temperature control accuracy of the product zone 101 and the test zone 102.

[0056] Preferably, the isolation groove 105 is a through groove that penetrates from top to bottom, and the upper end of the heat shielding ring 205 is not lower than the upper surface of the tray 1. This can further improve the heat insulation effect.

[0057] Furthermore, an annular mounting groove 206 may be provided between the first heating zone 201 and the second heating zone 202, and the lower end of the heat shielding ring 205 is inserted into the annular mounting groove 206 (eg, Figure 3 As shown), the heating interference between the first heating zone 201 and the second heating zone 202 can be better reduced.

[0058] The width of the heat shielding ring 205 can be set according to actual needs, but is not greater than the width of the isolation groove 105, for example, 4 mm.

[0059] The heat shielding ring 205 may be a solid circular ring made of heat insulating material.

[0060] The heat shielding ring 205 may also include an inner ring layer and an outer ring layer, with a gap between the inner ring layer and the outer ring layer.

[0061] The gap between the inner ring layer and the outer ring layer serves to block heat conduction. This structure can reduce the heat transfer between the first heating zone 201 and the second heating zone 202 (as well as the product zone 101 and the test zone 102), thereby better realizing the independent temperature control of the two heating zones. The air or vacuum layer in the gap can further reduce the efficiency of heat conduction. Through this improved heat shielding ring 205 structure, the temperature of the product zone 101 and the test zone 102 can be more effectively isolated, ensuring that the two zones can independently maintain the required temperature conditions. This is crucial for accurately controlling the temperature parameters during the molecular beam epitaxy growth process, which helps to improve the growth quality and product consistency.

[0062] The double-layer structure of the heat shielding ring 205 can be realized in many ways. For example, the inner ring layer and the outer ring layer can be made of the same or different materials. The inner ring layer can be made of a material with poor thermal conductivity, such as ceramic or special alloy, to further enhance the heat insulation effect. The outer ring layer can be made of a metal material that is resistant to high temperatures and has good stability.

[0063] The width of the gap can be adjusted according to specific needs. A wider gap can provide better insulation, but the stability of the overall structure and space limitations also need to be considered.

[0064] The inner and outer ring layers can be fixed together by special connection structures, such as connecting bridges at the top and bottom, to ensure the stability of the structure. These connecting parts can be made of materials with low thermal conductivity to reduce heat transfer.

[0065] In addition, special insulation materials can be filled in the gap, or reflective coatings can be applied to the surfaces of the inner and outer ring layers to further improve the insulation performance.

[0066] Specifically, see Figure 4 , Figure 5 The shielding device includes at least one shielding unit 3 , each shielding unit 3 includes a shielding piece 301 and a driving mechanism 302 , and the driving mechanism 302 is used to drive the shielding piece 301 to cover or move away from the test area 102 , thereby shielding or opening the second positioning groove 104 .

[0067] By controlling the movement of the shielding sheet 301 through the driving mechanism 302, the shielding and opening of the test area 102 can be realized. When the test area 102 needs to be shielded, the driving mechanism 302 drives the shielding sheet 301 to move to the upper side of the test area 102, so that the shielding sheet 301 covers the second positioning groove 104. When the test area 102 needs to be opened, the driving mechanism 302 drives the shielding sheet 301 away from the test area 102, so that the second positioning groove 104 is exposed.

[0068] This design can flexibly control the shielding state of the test area 102, so as to timely shield the second positioning groove 104 during the growth process, so that the required test structure is formed on the second substrate. At the same time, through the control of the shielding device, the formal product and the test structure can be grown simultaneously in the same growth process, which improves production efficiency and saves time and materials.

[0069] The shape of the shielding sheet 301 is adapted to the shape of the test area 102, and is specifically set according to the actual shape of the test area 102. The driving mechanism 302 can be a motor, a cylinder, or other device capable of achieving precise control. The number of shielding units 3 can be adjusted according to the size and shape of the test area 102 to achieve more precise shielding control.

[0070] For example, in the case where the test area 102 is an annular area, a plurality of shielding units 3 may be provided, and the shielding pieces 301 are arc-shaped shielding pieces. When all shielding pieces 301 cover the test area 102, the test area 102 can be completely covered (at this time, each shielding piece 301 forms an annular shielding structure that matches the test area 102, and the test area 102 is completely covered). For example, four shielding units 3 are provided, and are arranged at equal intervals around the tray 1, and the circumferential extension angle of the shielding pieces 301 is 90°.

[0071] The provision of multiple shielding units 3 can increase the coverage of the shielding device, so that it can more comprehensively shield the test area 102. The design of the arc-shaped shielding piece matches the annular structure of the test area 102, and can better fit the shape of the test area 102. Multiple arc-shaped shielding pieces work together to completely close the test area 102 when covering, avoiding the problem that a single shielding unit 3 cannot completely cover the test area 102.

[0072] The coordinated work of multiple shielding units 3 can achieve full coverage of the test area 102, and the shape design of the arc-shaped shielding piece ensures the strictness of the shielding. This design not only improves the shielding effect, but also enhances the control ability of the molecular beam epitaxy equipment over the test area 102 during the growth process, thereby improving the growth accuracy and reliability of the test structure.

[0073] The shielding sheet 301 may be made of a high temperature resistant material, such as molybdenum, tungsten or alloys thereof, to ensure stability in a high temperature environment.

[0074] Multiple shielding units 3 can be operated in a synchronous or sequential action mode. For example, in a synchronous action mode, all shielding units 3 can be moved into position at the same time to quickly complete the capping of the test area 102. In a sequential action mode, the shielding units 3 can be moved into position in sequence according to a preset order. This method can more accurately control the shielding process and is suitable for growth processes that require fine control.

[0075] In some possible implementations, see Figure 4 , Figure 5 One end of the shielding sheet 301 is provided with a stepped overlapping portion 3011. When shielding the test area 102, the other end of each shielding sheet 301 overlaps with the overlapping portion 3011 of the adjacent shielding sheet 301, thereby shielding the test area 102 more tightly.

[0076] As an example, see Figure 5 The driving mechanism 302 may include a connecting rod 3021, a driving device 3022 and a magnetic sleeve 3023. One end of the connecting rod 3021 is connected to the shielding sheet 301, and the other end is connected to the driving device 3022 through the magnetic sleeve 3023. The driving device 3022 is used to drive the connecting rod 3021 to drive the shielding sheet 301 to reciprocate along the radial direction of the tray 1. The driving device 3022 may be a motor, a cylinder or other power device.

[0077] In a second aspect, the present application provides a method for growing a vertical cavity surface laser. Based on the molecular beam epitaxy device described above, the method for growing a vertical cavity surface laser comprises the following steps: A1. Place a first substrate in the first positioning groove 103 of the tray 1, and place a second substrate in at least one second positioning groove 104; A2. Heat tray 1 to growth temperature; A3. When the shielding device opens the second positioning groove 104, the lower DBR structure and the active region are sequentially grown on the first substrate and the second substrate to form a test structure on the second substrate; A4. The second positioning groove 104 is closed by the shielding device, and the upper DBR structure continues to grow on the first substrate to form a formal product on the first substrate; A5. Take out the formal product and test structure after cooling down; A6. Perform structural tests on the test structure and adjust the growth parameters for the next round of growth based on the test results.

[0078] In step A1, the second substrate may be placed in only one second positioning groove 104, or in multiple second positioning grooves 104. When the second substrate is placed in multiple second positioning grooves 104, in step A6, the growth parameters for the next round of growth may be adjusted by combining the test results of multiple test structures, for example, calculating the mean of the same test parameter as the test result of the corresponding test parameter, and then adjusting the growth parameter according to the test result.

[0079] When a second positioning groove 104 is not used, a Si wafer can be placed in the unused second positioning groove 104 to cover the second positioning groove 104 and prevent raw materials from being directly deposited in the unused second positioning groove 104 and contaminating the second positioning groove 104 .

[0080] Among them, in step A2, by controlling the heating power of each heating zone of the heater 2, the tray 1 is heated according to a preset target heating curve until the growth temperature is reached (the growth temperature is set similarly according to the actual product material), and the temperature of the tray 1 is ensured to be uniform.

[0081] Among them, in step A3 and step A4, the growth process of the lower DBR structure, the active region and the upper DBR structure can adopt the existing technology, which will not be described in detail here.

[0082] Among them, in step A4, the heating power of the second heating zone 202 can be reduced or the heating of the second heating zone 202 can be stopped to reduce energy consumption, and at the same time, the heating power of the annular transition heating zone 204 can be increased to compensate for the temperature drop at the edge of the product zone 101, thereby maintaining the temperature uniformity and stability of the product zone 101.

[0083] Furthermore, when the temperature of the test area 102 drops below a preset safety temperature (such as 450° C.), the second positioning groove 104 can be covered by the shielding device to ensure the stability of the quality of the uppermost structure of the test structure and avoid damaging the structural integrity of the uppermost layer of the test structure when the shielding device covers the second positioning groove 104.

[0084] Among them, in step A5, during the cooling process, when the temperature of the product area 101 drops below the preset safety temperature (such as 450°C), the baffle of the V-group source furnace is closed to ensure the stability of the quality of the top structure of the formal product.

[0085] Among them, in step A6, the structural test may include an X-ray diffraction (XRD) test and a photoluminescence (PL) test to detect the wavelength and luminescence quality of the active region luminescence spectrum, as well as the thickness and composition of the DBR. The growth parameters are adjusted to make the detection parameters that deviate from the standard index return to the corresponding standard index. For example, the growth parameters can be adjusted according to expert experience, or the deviation value of each detection parameter from the standard index is input into a preset adjustment model, and the adjustment model calculates the adjustment amount of the growth parameter, and then the growth parameter is adjusted according to the adjustment amount.

[0086] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0087] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A molecular beam epitaxy apparatus comprising a growth chamber, characterized in that: Also includes: A tray (1), comprising a product area (101) and a test area (102), wherein the product area (101) is provided with at least one first positioning groove (103), the first positioning groove (103) being used to position and place a first substrate, the first substrate being used to grow a formal product, and the test area (102) is provided with at least one second positioning groove (104), the second positioning groove (104) being used to position and place a second substrate, the second substrate being used to grow a test structure; the test structure is identical to a portion of the growth structure of the formal product; A heater (2) disposed on the lower side of the tray (1) and used for heating the tray (1); The shielding device is capable of shielding and opening the second positioning groove (104), and is used to shield the second positioning groove (104) in a timely manner during the growth process, so that the test structure is formed on the second substrate in the second positioning groove (104).

2. The molecular beam epitaxy device according to claim 1, characterized in that: The product area (101) is a circular area located in the middle of the tray (1), and the test area (102) is an annular area surrounding the product area (101).

3. The molecular beam epitaxy device according to claim 2, characterized in that: The heater (2) comprises a first heating zone (201) for heating the product zone (101) and a second heating zone (202) for heating the test zone (102); the heating powers of the first heating zone (201) and the second heating zone (202) can be adjusted independently.

4. The molecular beam epitaxy apparatus according to claim 3, characterized in that: The first heating zone (201) comprises a main heating zone (203) located in the middle and an annular transition heating zone (204) surrounding the main heating zone (203), and the heating powers of the main heating zone (203) and the annular transition heating zone (204) can be adjusted independently.

5. The molecular beam epitaxy apparatus according to claim 3, characterized in that: An isolation groove (105) is provided between the product area (101) and the test area (102).

6. The molecular beam epitaxy apparatus according to claim 5, characterized in that: A heat shielding ring (205) is provided between the first heating zone (201) and the second heating zone (202), and the heat shielding ring (205) passes through the isolation groove (105).

7. The molecular beam epitaxy apparatus according to claim 6, characterized in that: The heat shielding ring (205) comprises an inner ring layer and an outer ring layer, and a gap is provided between the inner ring layer and the outer ring layer.

8. The molecular beam epitaxy apparatus according to claim 2, characterized in that: The shielding device comprises at least one shielding unit (3), each shielding unit (3) comprising a shielding sheet (301) and a driving mechanism (302), the driving mechanism (302) being used to drive the shielding sheet (301) to cover or move away from the test area (102), thereby shielding or opening the second positioning slot (104).

9. The molecular beam epitaxy apparatus according to claim 8, characterized in that: The shielding units (3) are provided in plurality, and the shielding sheets (301) are arc-shaped shielding sheets. When all the shielding sheets (301) cover the test area (102), the test area (102) can be completely covered.

10. A method for growing a vertical cavity surface laser, characterized in that: Based on the molecular beam epitaxy equipment according to any one of claims 1 to 9, the vertical cavity surface laser growth method comprises the steps of: A1. placing a first substrate in a first positioning groove (103) of a tray (1), and placing a second substrate in at least one of the second positioning grooves (104); A2. Heating the tray (1) to a growth temperature; A3. When the shielding device opens the second positioning groove (104), a lower DBR structure and an active region are sequentially grown on the first substrate and the second substrate, so that a test structure is formed on the second substrate; A4. covering the second positioning groove (104) by a shielding device, and continuing to grow an upper DBR structure on the first substrate, so that a formal product is formed on the first substrate; A5. After cooling down, take out the formal product and the test structure; A6. Perform structural testing on the test structure and adjust growth parameters for the next round of growth based on the test results.

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