A molecular beam epitaxy device and a vertical cavity surface laser growth method

Abstract

This application belongs to the field of molecular beam epitaxy equipment, and discloses a molecular beam epitaxy equipment and a method for growing vertical cavity surface emitting lasers. By simultaneously growing formal products and test structures on the same tray and using a shielding device to control the growth of the test structures, the problems in the prior art of separately growing test structures or complexly processing formal products are solved, and the advantages of saving time and raw materials, improving the control accuracy of growth parameters, and facilitating problem location are achieved.

Description

Technical Field

[0001] This application relates to the field of molecular beam epitaxy equipment. Specifically, it relates to a molecular beam epitaxy equipment and a method for growing vertical cavity surface emitting lasers. Background Art

[0002] A vertical cavity surface emitting laser (VCSEL) is a semiconductor laser in which light emits perpendicular to the surface of a semiconductor substrate. Compared with traditional edge-emitting lasers, VCSELs have multiple advantages, including low manufacturing cost, low threshold, low power consumption, good beam quality, small divergence angle, easy device coupling, high-speed modulation ability, and array integration. These advantages have made VCSELs widely concerned and valued in recent years.

[0003] The structure of a VCSEL mainly consists of multi-layer distributed Bragg reflectors (DBRs) on the upper and lower sides and a multi-layer quantum well / dot active region between the two DBR structures. Compared with most other microelectronic and optoelectronic devices, this complex structure poses greater challenges to the growth control and post-growth structure testing of VCSELs.

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

[0005] To ensure the repeatability and stability of growth, existing growth technologies usually require intermittently using test structures to adjust and calibrate growth parameters. The general approach is to insert a separate round of test structure growth after several complete rounds of VCSEL formal structure growth. This test structure usually only includes the lower DBR structure and the active region. This test structure is used for structure testing, and the test results are used for adjusting and calibrating growth parameters.

[0006] However, this method has some obvious drawbacks. First, in a production-type molecular beam epitaxy equipment, regardless of the number of wafers placed on a substrate carrier for growth, the same source furnace materials will be consumed. Therefore, if a process of growing only the test structure is inserted in the middle, it will cause waste of time and source materials. Second, due to slightly different growth conditions between different growth rounds, the test results of a single growth round cannot accurately reflect the equipment state during the growth of other rounds of formal structures, especially for growth parameters that require precise control. In addition, if there is a problem with the test structure, it is also difficult to determine which round of the previous formal structures had a problem.

[0007] Another prior art is to sample from a grown formal structure, remove the upper DBR structure through specific processing methods such as etching, and perform tests after exposing the active region. However, the processing of this method is rather cumbersome, 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, there is an urgent need for improvement in the prior art. Summary of the Invention

[0009] The purpose of the present application is to provide a molecular beam epitaxy device and a method for growing vertical cavity surface emitting lasers, 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, including a growth chamber, and further including:

[0011] A tray, which includes a product area and a test area. At least one first positioning groove is provided in the product area, and the first positioning groove is used to position and place a first substrate, and the first substrate is used for growing formal products. At least one second positioning groove is provided in the test area, and the second positioning groove is used to position and place a second substrate, and the second substrate is used for growing a test structure; the test structure has the same partial growth structure as the formal product;

[0012] A heater, which is arranged under the tray and is used to heat the tray;

[0013] A shielding device, which can shield and open the second positioning groove, and is used to shield the second positioning groove in a timely manner during the growth process, so as to form the test structure on the second substrate in the second positioning groove.

[0014] By simultaneously growing formal products and test structures on the same tray and using the shielding device to control the growth of the test structure, the problems in the prior art that require separate growth of test structures or complex processing of formal products are solved, and it has the advantages of saving time and source materials, improving the control accuracy of growth parameters, and facilitating problem location.

[0015] 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.

[0016] By setting the product area in the middle circular area, it can 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 an annular area surrounding the product area not only does not affect the growth of formal products but also enables the growth of test structures in the same batch. This layout realizes the synchronous growth of formal products and test structures, improves production efficiency, and saves time and material costs.

[0017] Preferably, the heater includes a first heating zone for heating the product area and a second heating zone for heating the test area; the heating powers of the first heating zone and the second heating zone can be independently adjusted.

[0018] By independently adjusting the powers of these two heating zones, the temperature uniformity of the tray can be better ensured, thereby improving the consistency of the growth conditions of each substrate.

[0019] Preferably, the first heating zone includes 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 independently adjusted.

[0020] Preferably, an isolation groove is provided between the product area and the test area.

[0021] Preferably, a thermal shielding ring is provided between the first heating zone and the second heating zone, and the thermal shielding ring passes through the isolation groove.

[0022] Preferably, the thermal shielding ring includes an inner ring layer and an outer ring layer, and there is a gap between the inner ring layer and the outer ring layer.

[0023] Preferably, the shielding device includes at least one shielding unit, and each shielding unit includes a shielding sheet and a driving mechanism, and the driving mechanism is used to drive the shielding sheet to cover or move away from the test area, so as to shield or open the second positioning groove.

[0024] Preferably, a plurality of the shielding units are provided, the shielding sheets are arc-shaped shielding sheets, and when all the shielding sheets cover the test area, the test area can be completely covered.

[0025] In a second aspect, the present application provides a method for growing a vertical cavity surface laser. Based on the molecular beam epitaxy equipment described above, the method for growing a vertical cavity surface laser includes the steps of:

[0026] A1. Place a first substrate in the first positioning groove of the tray, and place a second substrate in at least one of the second positioning grooves;

[0027] A2. Heat the tray to the growth temperature;

[0028] A3. In the case where the shielding device opens the second positioning groove, grow a lower DBR structure and an active region on the first substrate and the second substrate in sequence, so as to form a test structure on the second substrate;

[0029] A4. Shield the second positioning groove through a shielding device, and continue to grow the upper DBR structure on the first substrate, so as to form a formal product on the first substrate;

[0030] A5. Take out the formal product and the test structure after cooling;

[0031] A6. Conduct a structural test on the test structure, and adjust the growth parameters for the next round of growth according to the test results.

[0032] Beneficial effects: A molecular beam epitaxy device and a vertical cavity surface emitting laser growth method provided by the present application solve the problems in the prior art that a test structure needs to be grown separately or the formal product needs to be complexly processed 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, and have the advantages of saving time and raw materials, improving the control accuracy of growth parameters, and facilitating problem location. Description of the Drawings

[0033] Figure 1 It is a top view of the tray.

[0034] Figure 2 It is a top view of the heater.

[0035] Figure 3 It is a side view of the tray and the heater.

[0036] Figure 4 It is a top view of the shielding unit.

[0037] Figure 5 It is a side view of the shielding unit.

[0038] Figure 6 It is a flowchart of a vertical cavity surface emitting laser growth method.

[0039] Label description: 1. Tray; 101. Product area; 102. Test area; 103. First positioning groove; 104. Second positioning groove; 105. Isolation groove; 2. Heater; 201. First heating area; 202. Second heating area; 203. Main heating area; 204. Annular transition heating area; 205. Thermal 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 Embodiment

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying 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 the embodiments. The components of the embodiments of the present application usually described and illustrated in the accompanying 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 accompanying drawings is not intended to limit the scope of the present application claimed, but only represents the selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.

[0041] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, 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 the present application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0042] Vertical cavity surface emitting lasers (VCSELs) are an important type of semiconductor lasers, and their structure includes distributed Bragg reflectors (DBRs) on the upper and lower sides and a multi-layer quantum well / dot active region in the middle. Due to the complexity of the VCSEL structure, its growth control and structure testing face unique challenges. In the prior art, in order to ensure the repeatability and stability of growth, it is necessary to periodically grow and test test structures to adjust and calibrate growth parameters. However, this method has some problems.

[0043] Specifically, in a molecular beam epitaxy device, regardless of the number of wafers placed for growth, the same source furnace materials will be consumed. If a test structure is grown separately in one round, it will cause waste of time and materials. In addition, due to slightly different conditions between different growth rounds, the test structure grown separately cannot accurately reflect the device state during the growth of the formal structure. This makes it difficult to accurately adjust the growth parameters, affecting the production efficiency and quality control of VCSELs.

[0044] For this reason, please refer to Figures 1 - 5 , the present application provides a molecular beam epitaxy device, including a growth chamber, and further including:

[0045] Tray 1, which includes a product area 101 and a test area 102. At least one first positioning groove 103 is provided in the product area 101. The first positioning groove 103 is used to position and place a first substrate, and the first substrate is used for growing formal products (such as VCSEL products). At least one second positioning groove 104 is provided in the test area 102. The second positioning groove 104 is used to position and place a second substrate, and the second substrate is used for growing 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 region of the VCSEL product);

[0046] Heater 2, which is arranged on the lower side of the tray 1 and is used to heat the tray 1;

[0047] Blocking device, which can block and open the second positioning groove 104 and is used to timely block the second positioning groove 104 during the growth process, so that a test structure is formed on the second substrate in the second positioning groove 104.

[0048] By growing the formal product and the test structure simultaneously on the same tray 1 and using the blocking device to control the growth of the test structure, the problems in the prior art of separately growing the test structure or complexly processing the formal product are solved, and it has the advantages of saving time and raw materials, improving the control accuracy of growth parameters, and facilitating problem positioning.

[0049] Among them, the tray 1 refers to a platform structure for placing the substrate, and specifically can be realized in a disc shape made of metal materials or graphite and other materials.

[0050] Among them, the first positioning groove 103 and the second positioning groove 104 refer to groove structures on the tray 1 for fixing the substrate, and specifically can be realized by circular or square grooves matching the shape of the substrate. Among them, the size of the second positioning groove 104 can be less than or equal to the size of the first positioning groove 103, preferably less than the size of the first positioning groove 103. On the one hand, it will not affect the growth of each layer of the test structure, thus not affecting the test results, and on the other hand, it can save materials.

[0051] Among them, the heater 2 refers to a device for heating the tray 1, and specifically can be realized by a resistance heating element or a radiation heating element.

[0052] Among them, the blocking device refers to a mechanism for controlling the exposure state of the second positioning groove 104, and specifically can be realized by a movable blocking piece 301 and a driving mechanism 302.

[0053] Specifically, by setting the product area 101 and the test area 102 on the same tray 1 and cooperating with the use of the shielding device, the purpose of simultaneously growing formal products and test structures during a single growth process is achieved. This design not only improves the equipment utilization rate, reduces material waste, but also ensures that the test structure and the formal product are grown under the same conditions, improving the accuracy and representativeness of the test results. The specific usage process is as follows:

[0054] First, when growing the lower DBR structure and the active region, the second positioning groove 104 remains open, enabling the first substrate and the second substrate to receive molecular beams simultaneously. After the growth of the lower DBR structure and the active region is completed, 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.

[0055] Among them, the shapes and arrangement methods of the product area 101 and the test area 102 can be set according to actual needs.

[0056] In some possible implementation manners, 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.

[0057] By setting the product area 101 as a circular area in the middle, it can 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 an annular area surrounding the product area 101 neither affects the growth of the formal product nor can the growth of the test structure be carried out simultaneously in the same batch. This layout realizes the synchronous growth of the formal product and the test structure, improves production efficiency, and saves time and material costs.

[0058] In addition, the design of the annular test area 102 can also place multiple test substrates (i.e., the second substrate) at different positions, and the test results of the test structures at multiple different positions can be comprehensively used 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.

[0059] In some preferred implementation manners, see Figure 2 , Figure 3 , the heater 2 includes a first heating area 201 for heating the product area 101 and a second heating area 202 for heating the test area 102; the heating powers of the first heating area 201 and the second heating area 202 can be independently adjusted.

[0060] The first heating zone 201 is mainly responsible for heating the circular product area 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 area 102 surrounding the product area 101 to control the growth temperature of the test structure. By independently adjusting the power of these two heating zones, the temperature uniformity of the tray 1 can be better ensured, thereby improving the consistency of the growth conditions of each substrate.

[0061] Furthermore, as shown in 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 independently adjusted.

[0062] This design can more precisely 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 part of the product area 101. Since there may be heat loss in the edge part of the product area 101, the setting of the annular transition heating zone 204 can effectively compensate for this heat loss and ensure the temperature uniformity of the entire product area 101. In addition, when the growth of 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 temperature uniformity of the entire product area 101.

[0063] Among them, in order to more precisely control the temperature of each heating zone, temperature sensors 4 can be set at each heating zone (as shown in Figure 2 ). According to the measurement results of the temperature sensors 4, the heating powers of each heating zone are dynamically adjusted, so as to better ensure the temperature uniformity and ensure that the actual heating curve fits the required heating curve.

[0064] In some possible implementation manners, as shown in Figure 1 , an isolation groove 105 is provided between the product area 101 and the test area 102.

[0065] By setting the isolation groove 105, 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. Reducing the temperature interference between the product area 101 and the test area 102 can more accurately and stably control the temperatures of the two areas, and thus can better ensure the consistency of the temperature conditions of the substrates in the two areas.

[0066] The isolation groove 105 can be provided in various ways. For example, an annular groove can be directly machined on the tray 1, and this 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 requirements (for example, the width can be 1.5 cm) to achieve the best thermal isolation effect. Another possible implementation is to use a material with a lower thermal conductivity to fill the space between the product area 101 and the test area 102 to form a heat insulation layer.

[0067] Further, as shown in Figure 2 and Figure 3 , a thermal shielding ring 205 can be provided between the first heating zone 201 and the second heating zone 202, and the thermal shielding ring 205 passes through the isolation groove 105 (thus, the isolation groove 105 has a downward opening, and the upper part of the thermal shielding ring 205 extends into the isolation groove 105 from this opening).

[0068] The provision of the thermal shielding ring 205 can, on the one hand, reduce the heating interference between the first heating zone 201 and the second heating zone 202, and on the other hand, further reduce the heat transfer between the product area 101 and the test area 102, thereby further improving the temperature control accuracy of the product area 101 and the test area 102.

[0069] Preferably, the isolation groove 105 is a through groove that penetrates up and down, and the upper end of the thermal shielding ring 205 is not lower than the upper surface of the tray 1. Thereby, the heat insulation effect can be further improved.

[0070] Further, an annular mounting groove 206 can be provided between the first heating zone 201 and the second heating zone 202, and the lower end of the thermal shielding ring 205 is inserted into the annular mounting groove 206 (as Figure 3 shown), thereby better reducing the heating interference between the first heating zone 201 and the second heating zone 202.

[0071] Among them, the width of the thermal shielding ring 205 can be set according to actual needs, but it is not greater than the width of the isolation groove 105, for example, it is 4 mm.

[0072] Among them, the thermal shielding ring 205 can be a solid ring made of a heat insulation material.

[0073] The thermal shielding ring 205 can also include an inner ring layer and an outer ring layer, and there is a gap between the inner ring layer and the outer ring layer.

[0074] 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), thus better achieving independent temperature control of the two heating zones. The air or vacuum layer in the gap can further reduce the heat conduction efficiency. Through this improved structure of the thermal shielding ring 205, the temperatures 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 precisely controlling the temperature parameters during the molecular beam epitaxy growth process and helps improve the growth quality and product consistency.

[0075] The double-layer structure of the thermal shielding ring 205 can be achieved in various 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 materials with poor thermal conductivity, such as ceramics or special alloys, to further enhance the heat insulation effect. The outer ring layer can be made of metal materials with high temperature resistance and good stability.

[0076] The width of the gap can be adjusted according to specific requirements. A wider gap can provide better heat insulation, but the stability of the overall structure and space limitations also need to be considered.

[0077] The inner ring layer and the outer ring layer can be fixed together through special connection structures. For example, connection bridges can be set at the top and bottom to ensure the stability of the structure. These connection parts can be made of materials with low thermal conductivity to reduce heat transfer.

[0078] In addition, special heat insulation materials can be filled in the gap, or reflective coatings can be applied on the surfaces of the inner and outer ring layers to further improve the heat insulation performance.

[0079] Specifically, see Figure 4 、 Figure 5 The shielding device includes at least one shielding unit 3, and each shielding unit 3 includes a shielding piece 301 and a driving mechanism 302. The driving mechanism 302 is used to drive the shielding piece 301 to cover or move away from the test zone 102, thereby shielding or opening the second positioning groove 104.

[0080] By controlling the movement of the shielding piece 301 through the driving mechanism 302, the shielding and opening of the test zone 102 can be achieved. When it is necessary to shield the test zone 102, the driving mechanism 302 drives the shielding piece 301 to move to the upper side of the test zone 102, so that the shielding piece 301 covers the second positioning groove 104. When it is necessary to open the test zone 102, the driving mechanism 302 drives the shielding piece 301 to move away from the test zone 102, exposing the second positioning groove 104.

[0081] This design can flexibly control the occlusion state of the test area 102, thereby timely occluding 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 occlusion device, the formal product and the test structure can be grown simultaneously during the same growth process, improving production efficiency and saving time and materials.

[0082] Among them, the shape of the occlusion 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 devices capable of precise control. The number of the occlusion units 3 can be adjusted according to the size and shape of the test area 102 to achieve more precise occlusion control.

[0083] For example, in the case where the test area 102 is an annular area, multiple occlusion units 3 can be provided, and the occlusion sheet 301 is an arc-shaped baffle. When all the occlusion sheets 301 cover the test area 102, the test area 102 can be completely covered (at this time, each occlusion sheet 301 forms an annular occlusion structure adapted to the test area 102 to achieve the complete coverage of the test area 102). For example, four occlusion units 3 are provided and arranged at equal intervals around the tray 1, and the circumferential extension angle of the occlusion sheet 301 is 90°.

[0084] The setting of multiple occlusion units 3 can increase the coverage range of the occlusion device, enabling it to more comprehensively occlude the test area 102. The design of the arc-shaped baffle matches the annular structure of the test area 102 and can better fit the shape of the test area 102. Multiple arc-shaped baffles work together to completely enclose the test area 102 during covering, avoiding the problem that a single occlusion unit 3 cannot completely cover the test area 102.

[0085] The coordinated work of multiple occlusion units 3 can achieve the full coverage of the test area 102, and the shape design of the arc-shaped baffle ensures the tightness of the occlusion. This design not only improves the occlusion 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.

[0086] Among them, the occlusion sheet 301 can be made of high-temperature resistant materials such as molybdenum, tungsten or their alloys to ensure stability in a high-temperature environment.

[0087] Multiple occlusion units 3 can be operated in a synchronous or sequential manner. For example, in the synchronous action mode, all the occlusion units 3 can move into place simultaneously to quickly complete the covering of the test area 102. In the sequential action mode, the occlusion units 3 can move into place in a preset order, and this method can more precisely control the occlusion process and is suitable for growth processes that require fine control.

[0088] In some possible embodiments, 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 ends of the shielding sheets 301 are overlapped with the overlapping portions 3011 of the adjacent shielding sheets 301, so as to more tightly shield the test area 102.

[0089] 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 radially along the tray 1. The driving device 3022 may be a motor, a cylinder or other power devices.

[0090] In a second aspect, the present application provides a method for growing a vertical cavity surface emitting laser. Based on the molecular beam epitaxy equipment described above, the method for growing a vertical cavity surface emitting laser includes the steps of:

[0091] 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;

[0092] A2. Heat the tray 1 to the growth temperature;

[0093] A3. With the shielding device opening the second positioning groove 104, grow a lower DBR structure and an active region on the first substrate and the second substrate in sequence, so as to form a test structure on the second substrate;

[0094] A4. Close the second positioning groove 104 through the shielding device, and continue to grow an upper DBR structure on the first substrate, so as to form a formal product on the first substrate;

[0095] A5. Take out the formal product and the test structure after cooling;

[0096] A6. Perform a structure test on the test structure, and adjust the growth parameters of the next round of growth according to the test results.

[0097] Among them, in step A1, the second substrate may be placed in only one second positioning groove 104, or the second substrate may be placed in multiple second positioning grooves 104. When the second substrate is placed in multiple second positioning grooves 104, in step A6, the growth parameters of the next round of growth may be adjusted by comprehensively considering the test results of multiple test structures. For example, calculate the mean value of the same test parameter as the test result of the corresponding test parameter, and then adjust the growth parameters according to the test result.

[0098] When there is an unused second positioning groove 104, a Si wafer can be placed in the unused second positioning groove 104 to block the second positioning groove 104, preventing the raw material from directly depositing in the unused second positioning groove 104 and contaminating the second positioning groove 104.

[0099] 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 according to the actual product material), and the temperature of the tray 1 is ensured to be uniform.

[0100] Among them, in steps A3 and A4, the growth processes of the lower DBR structure, the active region, and the upper DBR structure can adopt existing technologies, and details are not described here.

[0101] 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. At the same time, the heating power of the annular transition heating zone 204 is increased to compensate for the temperature reduction at the edge of the product area 101, thereby maintaining the temperature uniformity and stability of the product area 101.

[0102] Furthermore, when the temperature of the test area 102 drops below the preset safe temperature (such as 450 °C), the second positioning groove 104 can be blocked by the shielding device. This ensures the quality stability of the uppermost layer structure of the test structure and avoids damaging the structural integrity of the uppermost layer of the test structure when the shielding device blocks the second positioning groove 104.

[0103] Among them, in step A5, during the cooling process, when the temperature of the product area 101 drops below the preset safe temperature (such as 450 °C), the V-group source furnace baffle is closed to ensure the quality stability of the uppermost layer structure of the formal product.

[0104] Among them, in step A6, the structure test can include X-ray diffraction (XRD) test and photoluminescence (PL) test to detect the wavelength and luminescence quality of the active region emission spectrum, as well as the thickness and composition of the DBR. The growth parameters are adjusted to make the detected parameters deviating from the standard indicators return to the corresponding standard indicators. For example, the growth parameters can be adjusted according to expert experience, or the deviation values of each detected parameter from the standard indicators are input into a preset adjustment model, and the adjustment amount of the growth parameters is calculated by the adjustment model, and then the growth parameters are adjusted according to the adjustment amount.

[0105] In this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0106] The above are only embodiments of the present application and are not intended to limit the protection scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within 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); a shielding device, capable of shielding and opening the second positioning groove (104), and used for shielding 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); 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.

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 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.

4. The molecular beam epitaxy apparatus according to claim 2, characterized in that: An isolation groove (105) is provided between the product area (101) and the test area (102).

5. The molecular beam epitaxy apparatus according to claim 4, 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).

6. The molecular beam epitaxy apparatus according to claim 5, 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.

7. 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).

8. The molecular beam epitaxy apparatus according to claim 7, 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.

9. 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 8, 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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