A method for growing multiple quantum wells, multiple quantum wells

Abstract

A method for growing multiple quantum wells is provided, the method comprising: P1: growing a barrier material In at a first temperature T1. a Ga 1‑a Material N; P2: Lowering the first temperature T1 to the second temperature T2, stopping or continuing the temperature change process. b Ga 1‑b Growth of N material; P3: Growth of the well layer material In at the second temperature T2. c Ga 1‑c Material N; P4: Raise the temperature from the second temperature T2 to the third temperature T3, and maintain In during the temperature change. d Ga 1‑d Growth of N material; P5: Growth of barrier material In at the third temperature T3. e Ga 1‑e Material N; repeat operations P2 to P5 sequentially, with N ≥ 1 repetition. This method, by setting the process of switching the growth conditions of the well layer material and the barrier layer material as a process of changing the growth temperature while maintaining material growth, is beneficial for improving the heterogeneous interface quality between the well / barrier materials in multi-quantum wells, and also for maintaining a high In composition in the well layer material, thereby improving device performance.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, and particularly relates to a method for growing multiple quantum wells and multiple quantum wells. Background Technology

[0002] The rapid development of the optoelectronic device manufacturing industry based on group III nitride (AlN, GaN, InN and their alloys) materials has not only greatly promoted the rapid popularization of semiconductor lighting technology, but also laid a solid foundation for the development of new display technologies. Among them, blue / green LEDs based on GaN materials are not only widely used in semiconductor lighting, but also play an important role in LCD TV backlighting, outdoor displays and other fields, especially the MiniLED and MicroLED technologies and products that have been rapidly maturing and being launched into the market in recent years.

[0003] With the increasing maturity of LED technology, GaN-based blue-green laser (LD) technology is also developing rapidly. Blue-green lasers have enormous application potential in fields such as laser TVs, laser lighting, and VR / AR / XR.

[0004] The most important manufacturing step for GaN-based LDs is the MOCVD epitaxial growth of the LD structure material. Among them, the growth of the InGaN / (In)GaN multi-quantum-well active region, which serves as the core light-emitting functional layer of the LD, is a key step that determines the performance of the entire LD device, especially important indicators such as electro-optical conversion efficiency, wavelength, and lifetime.

[0005] During the growth of the InGaN / (In)GaN multi-quantum-well active region, the incorporation efficiency of In decreases rapidly with increasing temperature. Therefore, in the process of growing InGaN material, it is necessary not only to grow at a lower temperature, but also to introduce an excessive amount of In source during the growth process to ensure that the In content in the InGaN material is sufficient so that the emission wavelength of the LD device meets the design requirements.

[0006] For green GaN-based lasers with a characteristic emission wavelength of 520 nm, the In content in the InGaN well layer of the InGaN / (In)GaN multi-quantum-well active region needs to be higher than 30%. Therefore, the growth conditions of the InGaN well layer not only require that the growth temperature not exceed 700 degrees, but also that there must be more than 100% excess In source in the gas phase.

[0007] The stringent requirements of the aforementioned growth conditions can easily lead to adverse consequences: First, the excessive supply of In source in the gas phase will result in a large amount of residual In in the reaction chamber, which will affect the growth of subsequent material layers; second, excess In atoms will be adsorbed and accumulated on the surface of the grown InGaN well layer material, which will damage the surface integrity and reduce the interface quality; third, the enrichment of In atoms on the material growth surface will affect and change the epitaxial growth mode of the material, resulting in reduced uniformity of the grown material and deterioration of photoelectric properties.

[0008] To eliminate the negative impact of In atoms enriching and accumulating on the material growth surface, the traditional method is to interrupt the growth of the InGaN well layer material after the growth is completed, and use a process of introducing hydrogen gas or raising the temperature and maintaining it for a period of time to remove the In enriched and accumulated on the growth surface of the InGaN well layer material, and then continue the epitaxial growth of subsequent material layers.

[0009] However, although the above-mentioned processing methods can remove excess In atoms from the surface of InGaN well layer materials, the interruption of growth, coupled with the increase in growth temperature at the same time, can easily lead to corresponding side effects: First, the integrity of the material surface will be severely damaged, especially the material surface where In atoms once accumulated; second, the In inside the InGaN well layer material will also diffuse and volatilize outward, resulting in a significant reduction in In content, making it difficult to obtain high-quality, high-In-content (e.g., more than 30%) InGaN well layer materials.

[0010] To mitigate the side effects of growth interruption and heating, a thin layer of less decomposed material, such as GaN, is typically grown after the InGaN well layer is completed. This layer covers the surface of the InGaN well layer to inhibit the outward diffusion of In atoms from within the InGaN well layer. Consequently, In atoms desorb from the InGaN surface and enter the gas phase, ensuring that the InGaN well layer maintains a high In content even after growth interruption and heating.

[0011] However, like the InGaN well layer material, the capping layer is grown at a relatively low temperature on a material surface with a large number of adsorbed and aggregated In atoms. This prevents the capping layer from growing in an optimal manner, and in some areas where In atoms have already accumulated, growth may not even be possible. The resulting capping layer may have a mesh structure and fail to completely cover the InGaN well layer material that needs protection. In areas of the InGaN well layer material surface not covered by the capping layer and still containing a large number of In atoms, these In atoms will desorb and detach from the InGaN material surface during subsequent heating processes, leaving pits or grooves of varying sizes and depths on the material surface. Therefore, the capping layer can only maintain the In content of a portion of the InGaN well layer material protected by the capping layer to a certain extent, and it cannot simultaneously improve the surface morphology of the material, and may even lead to interface quality deterioration. Summary of the Invention

[0012] To address the problems existing in the prior art, the present invention provides a method for growing multiple quantum wells and multiple quantum wells.

[0013] A method for growing multiple quantum wells according to one aspect of an embodiment of the present invention, wherein the multiple quantum wells are In x Ga 1-x N / In y Ga 1-y N quantum wells, where x > y, the method for growing multiple quantum wells includes: a first stage P1: growing In at a first temperature T1. a Ga 1-a Material N, where 0 ≤ a ≤ 0.5; Second stage P2: Lowering the first temperature T1 to the second temperature T2, stopping or continuing the temperature change process. b Ga 1-b The growth of N material, where 0 ≤ b ≤ 0.5; the third stage P3: at the second temperature T2, In is grown. c Ga 1-c Material N, where 0 < c ≤ 0.5; Fourth stage P4: The second temperature T2 is raised to the third temperature T3, and In is maintained during the temperature change. d Ga 1-d The growth of N material, where 0 ≤ d ≤ 0.5; Fifth stage P5: Growth of In at the third temperature T3. e Ga 1-e Material N, where 0 ≤ z ≤ 0.5; repeating the operations from the second stage P2 to the fifth stage P5 sequentially, for a total of N ≥ 1 repetitions, to obtain the In. x Ga 1-x N / Iny Ga 1-y Numerous quantum well structure materials.

[0014] In one example of the method for growing multiple quantum wells provided in one aspect of the above embodiments, 700°C < first temperature T1 < 950°C; and / or 600°C < second temperature T2 < 850°C; and / or 700°C < third temperature T3 < 950°C.

[0015] In one example of the method for growing multiple quantum wells provided in one aspect of the above embodiments, the second temperature T2 < the first temperature T1, and the second temperature T2 < the third temperature T3.

[0016] In one example of the method for growing multiple quantum wells provided in one aspect of the above embodiments, in the fourth stage P4, the growth temperature T R The process of raising the temperature from the second temperature T2 to the third temperature T3 includes the first heating process, the second heating process, ..., the (i-1)th heating process, and the ith heating process, where i is a positive integer.

[0017] In one example of the method for growing multiple quantum wells provided in one aspect of the above embodiments, during the i-th heating process, the growth temperature T Ri With the rate of change being K i It changes over time, where i is a positive integer.

[0018] In provided in one aspect of the above embodiments x Ga 1-x N / In y Ga 1-y In one example of a method for growing N-fold quantum well structure materials, during the i-th heating process, the second temperature T2 < the growth temperature T Ri ≤Third temperature T3, 0<rate of change K i <20℃ / s, where i is a positive integer.

[0019] In provided in one aspect of the above embodiments x Ga 1-x N / In y Ga 1-y In one example of a growth method for N-quantum well structure materials, in the fourth stage P4, the In d Ga 1-d The growth rate R of material N includes the first growth rate change process, the second growth rate change process, ..., the (j-1)th growth rate change process, and the jth growth rate change process, where j is a positive integer.

[0020] In provided in one aspect of the above embodiments xGa 1-x N / In y Ga 1-y In one example of a growth method for N-fold quantum well structure materials, during the j-th growth rate change, the growth rate R... j With the rate of change of velocity M j It changes over time, where j is a positive integer.

[0021] In provided in one aspect of the above embodiments x Ga 1-x N / In y Ga 1-y In one example of a growth method for N-fold quantum well structure materials, during the j-th growth rate change, 0 < growth rate R. j <20nm / s, 0 < rate of change of velocity M j <20nm / s 2 , where j is a positive integer.

[0022] The multi-quantum well provided according to another aspect of the present invention is grown by the above-described method for growing multi-quantum wells.

[0023] Beneficial Effects: The method for growing multiple quantum wells provided by this invention involves setting the process of switching the growth conditions of the well layer material and the barrier layer material into a temperature-changing process after the well layer material growth is completed, while maintaining material growth during this temperature change. By utilizing the temperature change to alter the migration ability of In atoms on the surface of the well layer material, the surface growth mode is controlled, thereby facilitating the acquisition of ideal surface morphology and improving interface quality. Furthermore, it simultaneously suppresses the outward diffusion and volatilization of In atoms in the well layer material, preventing them from escaping the well layer material surface and entering the gas phase, ensuring that the In content in the well layer material remains at a high level. It also avoids interface contamination caused by growth interruption, improving the luminescent performance of the material. In addition, it effectively avoids the influence of a large number of residual In atoms left in the reaction chamber during the preceding growth process on the growth mode of subsequent material layers, thus improving the crystal quality and electro-optic properties of the subsequently grown material layers. Therefore, the method for growing multiple quantum wells solves the problems of difficulty in maintaining a high In content in the well layer material, low heterogeneous interface quality, and elemental contamination between the two materials, thereby effectively improving the performance and electro-optic conversion efficiency of group III nitride optoelectronic devices. Attached Figure Description

[0024] The above and other aspects, features, and advantages of embodiments of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0025] Figure 1This is a flowchart of a method for growing multiple quantum wells according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the growth process of multiple quantum wells according to Embodiment 1 of the present invention;

[0027] Figure 3 This is a schematic diagram of the growth process of multiple quantum wells according to Embodiment 2 of the present invention;

[0028] Figure 4 This is a schematic diagram of the growth process of multiple quantum wells according to Embodiment 3 of the present invention;

[0029] Figure 5 This is a schematic diagram of the growth process of multiple quantum wells according to Embodiment 4 of the present invention. Detailed Implementation

[0030] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention can be implemented in many different forms, and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided to explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the various embodiments of the invention and various modifications suitable for particular intended applications.

[0031] As used herein, the term "comprising" and its variations are open terms meaning "including but not limited to". The terms "based on", "according to", etc., mean "at least partially based on" or "at least partially according to". The terms "one embodiment" and "an embodiment" mean "at least one embodiment". The term "another embodiment" means "at least one other embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other definitions, whether explicit or implicit, may be included below. Unless explicitly indicated by the context, the definition of a term remains consistent throughout the specification.

[0032] As described in the background section, existing technologies use a capping layer to eliminate the negative effects of In atom enrichment and aggregation on the surface of the well layer material. However, this method can only maintain the In content in a portion of the well layer material protected by the capping layer to a certain extent, and it cannot simultaneously improve the surface morphology of the material, and may even lead to interface quality deterioration. Therefore, in order to solve the above-mentioned technical problems in the prior art, an embodiment of the present invention provides a method for growing multiple quantum wells and multiple quantum wells.

[0033] The method for growing multiple quantum wells involves setting the process of switching the growth conditions of the well layer material and the barrier layer material as a process of changing the growth temperature after the well layer material has been grown. During this temperature change, the material growth continues, which helps to improve the quality of the heterogeneous interface between the two materials in the multiple quantum wells, and at the same time maintains the In content in the well layer material at a high level, thereby helping to improve the performance of the device.

[0034] The method for growing multiple quantum wells according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. Figure 1 This is a flowchart of a method for growing multiple quantum wells according to an embodiment of the present invention, with reference to... Figure 1 .

[0035] In step S110, the first stage P1: at the first temperature T1, In grows a Ga 1-a Material N, where 0 ≤ a ≤ 0.5.

[0036] In this embodiment, 700℃ < first temperature T1 < 950℃.

[0037] Specifically, in the growth of the In a Ga 1-a In the process of producing N materials, nitrogen is used as the carrier gas, high-purity ammonia is used as the group V source, and a mixture of trimethylgallium / dimethylgallium and trimethylindium is used as the group III source; the growth pressure is 0-2 MPa and the growth rate is no more than 10 nm / s.

[0038] The In a Ga 1-a N (0≤a≤0.5) material serves as a barrier layer for multiple quantum wells, restricting the spatial distribution and movement of charge carriers along the material growth direction.

[0039] In step S120, the second stage P2: the first temperature T1 is reduced to the second temperature T2, and the process of temperature change is stopped or continued. b Ga 1-b The growth of N-material, where 0 ≤ b ≤ 0.5.

[0040] In this embodiment, 600℃ < second temperature T2 < 850℃, and second temperature T2 < first temperature T1.

[0041] Specifically, in the growth of the In b Ga 1-b In the process of producing N materials, nitrogen is used as the carrier gas, high-purity ammonia is used as the group V source, and trimethylgallium or a mixture of dimethylgallium and trimethylindium is used as the group III source; the growth pressure is 0-2 MPa and the growth rate is no more than 10 nm / s.

[0042] Maintain or stop In during the process of lowering the first temperature T1 to the second temperature T2 b Ga 1-b The growth of N (0≤b≤0.5) material aims to improve the surface morphology of the material and prepare for the subsequent growth of the trap layer material.

[0043] In step S130, the third stage P3: at the second temperature T2, In grows c Ga 1-c Material N, where 0 < c ≤ 0.5.

[0044] Specifically, in the growth of the In c Ga 1-c In the process of producing N materials, nitrogen is used as the carrier gas, high-purity ammonia is used as the group V source, and a mixture of trimethylgallium / dimethylgallium and trimethylindium is used as the group III source; the growth pressure is 0-2 MPa and the growth rate is no more than 10 nm / s.

[0045] The In c Ga 1-c N material serves as the well layer in a multi-quantum-well system, wherein In c Ga 1-c The N-well layer material serves as the main distribution and recombination emission region for charge carriers, and is the main functional layer of the device.

[0046] In step S140, the fourth stage P4: the second temperature T2 is raised to the third temperature T3, and In is maintained during the temperature change. d Ga 1-d The growth of N-material, where 0 ≤ d ≤ 0.5.

[0047] In this embodiment, 700℃ < third temperature T3 < 950℃, and second temperature T2 < third temperature T3.

[0048] Among them, in the growth of the In d Ga 1-d In the process of producing N materials, nitrogen is used as the carrier gas, high-purity ammonia is used as the group V source, and a mixture of trimethylgallium / dimethylgallium and trimethylindium is used as the group III source; the growth pressure is 0-2 MPa.

[0049] Specifically, in the fourth stage P4, the growth temperature T R The temperature is increased from the second temperature T2 to the third temperature T3, and the growth temperature T R The process of change over time includes the first heating process, the second heating process, ..., the (i-1)th heating process, and the ith heating process, where i is a positive integer.

[0050] In the i-th heating process, the growth temperature T Ri With the rate of change being K i It changes over time, where i is a positive integer.

[0051] In one example, during the i-th heating process, the second temperature T2 < the growth temperature T Ri ≤Third temperature T3, 0<rate of change K i <20℃ / s, where i is a positive integer.

[0052] In the fourth stage P4, when the growth temperature T is... R When the process of heating from the second temperature T2 to the third temperature T3 is divided into multiple heating processes, the rate of change of two adjacent heating processes in the multiple heating processes is not the same, and the rate of change of two non-adjacent heating processes can be the same or different.

[0053] Specifically, in the fourth stage P4, the In d Ga 1-d The growth rate R of material N changes over time, including the first growth rate change process, the second growth rate change process, ..., the (j-1)th growth rate change process, and the jth growth rate change process, where j is a positive integer.

[0054] Wherein, during the j-th growth rate change process, the growth rate R j With the rate of change of velocity M j It changes over time, where j is a positive integer.

[0055] In one example, during the j-th growth rate change, 0 < growth rate R j <20nm / s, 0 < rate of change of velocity M j <20nm / s 2 , where j is a positive integer.

[0056] In the fourth stage P4, when the change of growth rate R over time is divided into multiple growth rate change processes, the rate of change of two adjacent growth rate change processes in the multiple growth rate change processes are not the same, and the rate of change of two non-adjacent growth rate change processes can be the same or different.

[0057] In the j-th growth rate change process, the growth rate change is achieved by increasing the temperature, changing the pressure in the growth chamber, and adjusting the proportions of various gases required for material growth to regulate the growth pattern on the material surface. In addition, the growth rate change can also be achieved by adjusting the flow rate of the gas source material required for material growth.

[0058] The method for growing multiple quantum wells involves completing the growth of In in the third stage P3. c Ga 1-c Following the N-well layer material, and before starting the fifth stage of P5 growth In e Ga 1-e Before the N-layer material, the growth temperature change process continues from the fourth stage P4, and during this temperature change process, In is still maintained. d Ga 1-d The growth of N (0≤d≤0.5) materials has the following advantages: First, it effectively avoids the influence of a large number of residual In atoms left in the reaction chamber during the previous growth process on the growth mode of subsequent material layers, thereby improving the crystal quality and electro-optic properties of the subsequently grown material layers. Second, increasing the temperature can enhance the surface migration ability of In atoms, thereby reducing the surface migration of In atoms in the In... c Ga 1-c The increased aggregation of In atoms on the surface of the N-well layer material improves the uniformity of In atom distribution on the growth surface, thereby enhancing the smoothness and integrity of the interface. Furthermore, the In atoms remain stable even with temperature changes. d Ga 1-d The growth of N materials can enable In c Ga 1-c In the N-well layer material, some of the desorbed In atoms enter the newly grown material layer, which not only improves the utilization efficiency of In but also inhibits the outward diffusion and volatilization of In atoms. c Ga 1-c The N-well layer material enters the gas phase from its surface, thus helping to maintain In. c Ga 1-c The high In content in the N-well layer material is a key advantage. Thirdly, it avoids interface contamination caused by growth interruption, thus improving the material's luminescence performance. Fourthly, by gradually increasing the growth temperature and using a suitable growth rate, the epitaxial growth mode of the material can be altered, which is beneficial for improving the In content. d Ga 1-d The quality of the N material layer is improved, which in turn helps to enhance the luminescence performance of the quantum well.

[0059] In step S150, the fifth stage P5: at the third temperature T3, In is grown. e Ga 1-e Material N, where 0 ≤ e ≤ 0.5.

[0060] Specifically, in the growth of the In e Ga 1-eIn the process of the material, nitrogen is used as the carrier gas, high-purity ammonia is used as the group-V source, and a mixture of trimethylgallium / dimethylgallium and trimethylindium is used as the group-III source; wherein, the growth pressure is 0 to 2 MPa, and the growth rate is not more than 10 nm / s.

[0061] The In e Ga 1-e N material (0 ≤ e ≤ 0.5) is used as the barrier layer of the multiple quantum wells, which can restrict the spatial distribution and movement of carriers in the material growth direction. <​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Step 3, the third stage P3: At the second temperature T2, for growing In c Ga 1-c N (0 < c ≤ 0.5) material, as the well layer of the multiple quantum well.

[0071] Step 4, the fourth stage P4: Raise the second temperature T2 to the third temperature T3, and maintain the growth of the GaN material during the temperature change process, where 700 °C < T3 < 950 °C, and T2 < T3, and T3 = T1.

[0072] Specifically, in the fourth stage P4, the growth temperature T R is raised from the second temperature T2 to the third temperature T3, and the growth temperature T R The change process with time includes 1 heating process, that is, the growth temperature T R changes linearly with time at a change rate of K, that is, the relationship between the growth temperature T R and time t is: T R = T2 + K * t, where T2 < T R ≤ T3, 0 < K < 20 °C / s.

[0073] In the fourth stage P4, the change process of the growth rate R of the GaN material with time includes 1 growth rate change process. That is, the growth rate R changes linearly with time at a rate change rate of M, that is, the relationship between the growth rate R and time t is: R = R0 + M * t, where R0 is the initial growth rate of the GaN material in the fourth stage; where, 0 < M < 20 nm / s 2 , 0 < R0 < 20 nm / s, 0 < R < 20 nm / s.

[0074] In the fourth stage P4, the time required for this process is appropriately set according to the heating system capacity and thermal load characteristics of the growth equipment.

[0075] Step 5, the fifth stage P5: At the third temperature T3, grow GaN material as the barrier layer of the multiple quantum well; the growth conditions such as the growth temperature and growth rate of this GaN barrier layer material can be different from those in the P1 stage.

[0076] Sequentially repeat the growth stages of Step 2 to Step 5, and the number of repetitions N (N ≥ 1) meets the device performance requirements according to the device structure design requirements.

[0077] <Example of Embodiment 2>

[0078] The multiple quantum well in this embodiment is an In x Ga 1-x N / GaN (0 < x ≤ 0.5) multiple quantum well, where the number of periods of the multiple quantum well is not less than 2.

[0079] Figure 3 is a schematic diagram of the growth process of a multi - quantum well according to Embodiment 2 of the present invention. Referring together to Figure 1 and Figure 3 , the process of growing the In x Ga 1-x N / GaN (0 < x ≤ 0.5) multi - quantum well specifically includes:

[0080] Step 1, First stage P1: At the first temperature T1, GaN material is grown as the first barrier layer of the multi - quantum well, where 700 °C < T1 < 950 °C.

[0081] Step 2, Second stage P2: The first temperature T1 is reduced to the second temperature T2, and the growth of GaN material is stopped during this temperature change, where 600 °C < T2 < 850 °C and T2 < T1. During this process, according to the thermal load characteristics of the growth equipment, the temperature change rate or time is appropriately controlled to ensure that while the temperature changes rapidly, it stabilizes at the temperature required for the subsequent material growth as quickly as possible.

[0082] [[ID=二十]]Step 3, Third stage P3: At the second temperature T2, In c Ga 1-c N (0 < c ≤ 0.5) material is grown as the well layer of the multi - quantum well structure.

[0083] Step 4, Fourth stage P4: The second temperature T2 is raised to the third temperature T3, and the growth of GaN material is maintained during the temperature change, where 700 °C < T3 < 950 °C, and T2 < T3, T = T1, and T = T1. <000,0396>

[0084] In the fourth stage P4, the growth temperature T R is raised from the second temperature T2 to the third temperature T3. The change process of the growth temperature T R with time includes the first heating process and the second heating process.

[0085] Specifically, in the first heating process, the growth temperature T R1 changes linearly with time t at a change rate of K1, that is, the relationship between the growth temperature T R1 and time t is: T R1 = T2 + K1 * t, where 0 < K1 < 20 °C / s, T2 < T R1 < T3.

[0086] In the second heating process, the growth temperature T R2 changes linearly with time t at a change rate of K2, that is, the growth temperature T R2The relationship between T and time t is as follows: R2 = (T2 + K1 * Δt1) + K2 * t, where Δt1 is the time required for the first heating process, and 0 <K2<20℃ / s,T2<T R2 ≤T3.

[0087] In the fourth stage P4, the growth rate R of the GaN material changes over time, including one growth rate change process. That is, the growth rate R changes linearly with time at a rate of change M, specifically, the relationship between the growth rate R and time t is: R = R0 + M * t, where R0 is the initial growth rate of the GaN material in the fourth stage; where 0... <M<20nm / s 2 0 <R0<20nm / s,0<R<20nm / s。

[0088] In the fourth stage P4, the time required for this process is appropriately set according to the heating system capacity and thermal load characteristics of the growth equipment.

[0089] Step 5, Fifth Stage P5: At the third temperature T3, GaN material is grown as a barrier layer for multiple quantum wells; the growth conditions such as the growth temperature and growth rate of this GaN barrier layer material can be different from those in stage P1.

[0090] The growth stages described in steps two through five are repeated sequentially, with the number of repetitions N (N≥1) to meet the device performance requirements according to the device structure design.

[0091] <Example 3>

[0092] In this embodiment, the multiple quantum well is In x Ga 1-x N / In y Ga 1-y N (0 < x, y ≤ 0.5, x > y) multiple quantum wells, wherein the number of periods of the multiple quantum wells is not less than 2.

[0093] Figure 4 This is a schematic diagram of the growth process of multiple quantum wells according to Embodiment 3 of the present invention, and is also referred to. Figure 1 and Figure 4 , growth of the In x Ga 1-x N / In y Ga 1-y The process of N (0 < x, y ≤ 0.5, x > y) multiple quantum wells specifically includes:

[0094] Step 1, First Stage P1: GaN material is grown at a first temperature T1 as the first barrier layer for multiple quantum wells, at 700℃. <T1<950℃。

[0095] Step 2, the second stage P2: Lower the first temperature T1 to the second temperature T2, and stop the growth of the GaN material during this temperature change, where 600 °C < T2 < 850 °C, and T2 < T1. During this process, according to the thermal load characteristics of the growth equipment, appropriately control the temperature change rate or time to ensure that while the temperature changes rapidly, it stabilizes at the temperature required for subsequent material growth as quickly as possible.

[0096] Step 3, the third stage P3: At the second temperature T2, for growing In c Ga 1-c N (0 < c ≤ 0.5) material as the well layer of the multi-quantum well structure.

[0097] Step 4, the fourth stage P4: Raise the second temperature T2 to the third temperature T3, and maintain the growth of In d Ga 1-d N (0 < d ≤ 0.5) material during the temperature change, where 700 °C < T3 < 950 °C, and T2 < T3, and T3 = T1.

[0098] Specifically, in the fourth stage P4, during the growth temperature T R rising from the second temperature T2 to the third temperature T3, the change process of the growth temperature T R with time includes 1 heating process, that is, the growth temperature T R varies linearly with time at a change rate of K, that is, the relationship between the growth temperature T R and time t is: T R = T2 + K * t, where T2 < T R ≤ T3, 0 < K < 20 °C / s.

[0099] In the fourth stage P4, the change process of the growth rate R of the In d Ga 1-d N material with time includes the first growth rate change process and the second growth rate change process. <000043​​​​​​​​​​In the second growth rate change process, the growth rate R2 changes linearly with time at a rate of change of M2, that is, the relationship between the growth rate R2 and time t is: R2=(R0+M1*Δt1)+M2*t, where Δt1 is the time required for the first growth rate change process, where 0 <M2<20nm / s 2 ;0 <R2<20nm / s。

[0102] In the fourth stage P4, the time required for this process is appropriately set according to the heating system capacity and thermal load characteristics of the growth equipment.

[0103] Step 5, Fifth Stage P5: Growing In at the third temperature T3 e Ga 1-e N (0 < e ≤ 0.5) material is used as a barrier layer for multiple quantum wells; this In e Ga 1-e The growth conditions, such as growth temperature and growth rate, for N-barrier layer materials can differ from those in the P1 stage.

[0104] The growth stages described in steps two through five are repeated sequentially, with the number of repetitions N (N≥1) to meet the device performance requirements according to the device structure design.

[0105] <Example 4>

[0106] In this embodiment, the multiple quantum well is In x Ga 1-x N / In y Ga 1-y N (0 < x, y ≤ 0.5, x > y) multiple quantum wells, wherein the number of periods (M) of the multiple quantum wells is not less than 2.

[0107] Figure 5 This is a schematic diagram of the growth process of multiple quantum wells according to Embodiment 5 of the present invention, and is also referred to. Figure 1 and Figure 5 , growth of the In x Ga 1-x N / In y Ga 1-y The process of N (0 < x, y ≤ 0.5, x > y) multiple quantum wells specifically includes:

[0108] Step 1, First Stage P1: GaN material is grown at a first temperature T1 as the first barrier layer for multiple quantum wells, at 700℃. <T1<950℃。

[0109] Step 2, Second stage P2: Lower the first temperature T1 to the second temperature T2. During this temperature change process, stop the growth of the GaN material, where 600 °C < T2 < 850 °C and T2 < T1. During this process, according to the thermal load characteristics of the growth equipment, appropriately control the temperature change rate or time to ensure that while the temperature changes rapidly, it stabilizes at the temperature required for subsequent material growth as quickly as possible.

[0110] Step 3, Third stage P3: At the second temperature T2, grow In c Ga 1-c N (0 < c ≤ 0.5) material as the well layer of the multi-quantum well structure.

[0111] Step 4, Fourth stage P4: Raise the second temperature T2 to the third temperature T3. During the temperature change process, maintain the growth of In d Ga 1-d N (0 < d ≤ 0.5) material, where 700 °C < T3 < 950 °C, T2 < T3, and T3 = T1.

[0112] In the fourth stage P4, during the process of the growth temperature T R rising from the second temperature T2 to the third temperature T3, the change process of the growth temperature T R with time includes the first heating process and the second heating process.

[0113] Specifically, in the first heating process, the growth temperature T R1 varies linearly with time t at a change rate of K1, that is, the relationship between the growth temperature T<000018-six]][[ID=]with time t is: T R1 = T2 + K1 * t, where 0 < K1 < 20 °C / s, T2 < T R1 < T3.

[0114] In the second heating process, the growth temperature T R2 varies linearly with time t at a change rate of K2, that is, the relationship between the growth temperature T R2 with time t is: T R2 = (T2 + K1 * Δt1) + K2 * t, Δt1 is the time required in the first heating process, where 0 < K2 < 20 °C / s, T < T R2 ≤ T3, and T R1 < T R2 .

[0115] In the fourth stage P4, the In d Ga 1-dThe change process of the growth rate R of N material over time includes the first growth rate change process and the second growth rate change process.

[0116] Specifically, in the first growth rate change process, the growth rate R1 linearly changes with time at a rate change rate of M1, that is, the relationship between the growth rate R1 and time t is: R1 = R0 + M1 * t, where R0 is the initial growth rate of In d Ga 1-d N material, 0 < M1 < 20 nm / s 2 ; 0 < R0 < 20 nm / s, 0 < R1 < 20 nm / s, and R0 < R1.

[0117] In the second growth rate change process, the growth rate R2 linearly changes with time at a rate change rate of M2, that is, the relationship between the growth rate R2 and time t is: R1 = (R0 + M1 * Δt1) + M2 * t, where Δt1 is the time required in the first growth rate change process, and 0 < M2 < 20 nm / s 2 ; 0 < R2 < 20 nm / s, and R1 < R2.

[0118] In the fourth stage P4, the time required in this process is appropriately set according to the heating system capacity and heat load characteristics of the growth equipment.

[0119] Step Five, the fifth stage P5: At the third temperature T3, grow In e Ga 1-e N(0 < e ≤ 0.5) material as the barrier layer of the multi - quantum well; the growth conditions such as the growth temperature and growth rate of this In e Ga 1-e N barrier layer material can be different from those in the P1 stage.

[0120] Sequentially repeat the growth stages described in Step Two to Step Five, and the number of repetitions N (N ≥ 1) meets the device performance requirements according to the device structure design requirements.

[0121] According to another aspect of the embodiment of the present invention, a multi - quantum well is provided, which is grown by the method of growing a multi - quantum well as described above. [[ID=3X]]<0XXXXX>

[0122] In summary, the present invention provides a method for growing In x Ga 1-x N / In y Ga 1-yThe multiple quantum well method involves a temperature change process following the transition between the well and barrier layer materials after the well layer material growth is complete, while maintaining material growth throughout this temperature change. By utilizing the temperature variation to alter the migration ability of In atoms on the well layer surface, the surface growth mode is controlled, thereby facilitating the acquisition of ideal surface morphology and improving interface quality. Furthermore, it simultaneously suppresses the outward diffusion and volatilization of In atoms from the well layer material, preventing them from escaping the well layer surface and entering the gas phase, ensuring that the In content in the well layer material remains at a high level. It also avoids interface contamination caused by growth interruption, improving the material's luminescence properties. In addition, it effectively prevents the large amount of residual In atoms left in the reaction chamber during the preceding growth process from affecting the growth mode of subsequent material layers, thus contributing to improved crystal quality and electro-optic properties of the subsequently grown material layers.

[0123] Therefore, the growth In x Ga 1-x N / In y Ga 1-y The N-quantum-well method solves the problems of maintaining a high In content in the well layer material, low heterogeneous interface quality, and elemental contamination between the two quantum well materials, thereby effectively improving the performance and electro-optical conversion efficiency of group III nitride optoelectronic devices.

[0124] The foregoing has described specific embodiments of the invention. Other embodiments are within the scope of the appended claims.

[0125] The terms “exemplary,” “example,” etc., used throughout this specification mean “serving as an example, instance, or illustration” and do not imply “preferred” or “advantageous” than other embodiments. Detailed descriptions are included for the purpose of providing an understanding of the described techniques. However, these techniques can be practiced without these detailed descriptions. In some instances, well-known structures and apparatuses are shown in block diagram form to avoid obscuring the concepts of the described embodiments.

[0126] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention.

[0127] The foregoing description of this specification is provided to enable any person skilled in the art to implement or use the content of this specification. Various modifications to the content of this specification will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of protection of this specification. Therefore, this specification is not limited to the examples and designs described herein, but is consistent with the widest scope of the principles and novel features disclosed herein.

Claims

1. A method for growing multiple quantum wells, characterized in that, The multiple quantum well is In x Ga 1-x N / In y Ga 1-y N quantum wells, where x > y, the method for growing multiple quantum wells includes: Phase 1 P1: Growth of In at the first temperature T1 a Ga 1-a Material N, where 0 ≤ a ≤ 0.5; Second stage P2: Lower the first temperature T1 to the second temperature T2, stopping or continuing the temperature change process. b Ga 1-b The growth of N-material, where 0 ≤ b ≤ 0.5; Phase 3 P3: At the second temperature T2, In grows... c Ga 1-c Material N, where 0 < c ≤ 0.5; Phase 4 P4: Increase the temperature from the second temperature T2 to the third temperature T3, maintaining In during the temperature change. d Ga 1-d The growth of N-material, where 0 ≤ d ≤ 0.5; Fifth stage P5: At the third temperature T3, In is grown. e Ga 1-e Material N, where 0 ≤ e ≤ 0.5; The operations of the second stage P2 to the fifth stage P5 are repeated sequentially, with N ≥ 1 repetitions, to obtain the In. x Ga 1-x N / In y Ga 1-y Numerous quantum wells; Among them, in the completion of the third stage P3 growth In c Ga 1-c Following the N-well layer material, and before starting the fifth stage of P5 growth In e Ga 1-e Before the N-barrier layer material, the growth temperature change process continues from the fourth stage P4, during which In is continuously maintained. d Ga 1-d The growth of N-material, where 0 < d ≤ 0.

5.

2. The method for growing multiple quantum wells according to claim 1, characterized in that, 700℃ < first temperature T1 < 950℃; and / or 600℃ < second temperature T2 < 850℃; and / or 700℃ < third temperature T3 < 950℃.

3. The method for growing multiple quantum wells according to claim 2, characterized in that, The second temperature T2 < the first temperature T1, and the second temperature T2 < the third temperature T3.

4. The method for growing multiple quantum wells according to any one of claims 1 to 3, characterized in that, In the fourth stage P4, the growth temperature T R The temperature is increased from the second temperature T2 to the third temperature T3, and the growth temperature T R The process of change over time includes the first heating process, the second heating process, ..., the (i-1)th heating process, and the ith heating process, where i is a positive integer.

5. The method for growing multiple quantum wells according to claim 4, characterized in that, During the i-th heating process, the growth temperature T Ri With the rate of change being K i It changes over time, where i is a positive integer.

6. The method for growing multiple quantum wells according to claim 5, characterized in that, During the i-th heating process, the second temperature T2 < the growth temperature T Ri ≤Third temperature T3, 0<rate of change K i <20℃ / s, where i is a positive integer.

7. The method for growing multiple quantum wells according to any one of claims 1 to 3, characterized in that, In the fourth stage P4, the In d Ga 1-d The growth rate R of material N changes over time, including the first growth rate change process, the second growth rate change process, ..., the (j-1)th growth rate change process, and the jth growth rate change process, where j is a positive integer.

8. The method for growing multiple quantum wells according to claim 7, characterized in that, During the j-th growth rate change process, the growth rate R j With the rate of change of velocity M j It changes over time, where j is a positive integer.

9. The method for growing multiple quantum wells according to claim 8, characterized in that, During the j-th growth rate change process, 0 < growth rate R j <20nm / s, 0 < rate of change of velocity M j <20nm / s 2 , where j is a positive integer.

10. A multi-quantum well grown by the method for growing multi-quantum wells according to any one of claims 1 to 9.

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