MOCVD (Metal Organic Chemical Vapor Deposition) equipment deposition method based on digital twinborn model

Abstract

The invention discloses an MOCVD (Metal Organic Chemical Vapor Deposition) equipment deposition method based on a digital twinborn model, which comprises the following steps of: 1, establishing a digital twinborn geometric model of MOCVD equipment according to the structure and size conditions of the actual MOCVD equipment, and 2, constructing a simulated digital twinborn model; 3, performing numerical simulation on the digital twinning geometric model through a process parameter data range and CFD to obtain flow state data corresponding to different process parameters and a simulated growth rate in the flow state; 4, correcting the simulated growth rate; 5, acquiring laminar flow and turbulent flow state diagrams under different process parameters, and forming a visual chemical control platform; and 6, depositing the product in the MOCVD equipment. According to the method, the digital twin with the stable MOCVD cavity is constructed, a visual and interactive visual platform is established, design and optimization of a high-quality epitaxial material are jointly guided by a digital model and an experiment, and a theoretical basis is provided for research and development of a high-quality, high-efficiency and high-reliability thin film epitaxial technology and high-end oxide semiconductor MOCVD equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of MOCVD equipment deposition, and specifically to a MOCVD equipment deposition method based on a digital twin model. Background Art

[0002] The popularity of digital twins continues to rise, and they frequently appear in speeches at major summits and forums, attracting much attention from both inside and outside the industry. In 2015, General Electric realized real-time monitoring, inspection and maintenance of engines based on digital twins. Gartner has listed digital twins as one of the top ten strategic technology development trends for three consecutive years.

[0003] The emergence of digital twin technology will greatly promote the development of equipment and material design. Digital twins make full use of data such as physical models, sensor updates, and operation history, integrate multi-disciplinary, multi-physical, multi-scale, and multi-probability simulation processes, and complete mapping in virtual space, thereby reflecting the entire life cycle of the corresponding physical equipment. Digital twins are a universally applicable theoretical and technical system that is widely used in military, medical, manufacturing and other fields. Its goal is to accurately map the physical information of the real space and present it to managers for relevant decision-making.

[0004] Therefore, the research on chamber stability of MOCVD multi-process parameter coupling mechanism based on digital twin technology will reveal the fluid state inside the MOCVD chamber, explore the relationship between the gas transport process in the reaction chamber under the coupling of multiple fields (flow field, temperature field, chemical field, component concentration field, etc.) generated under multiple process parameters (inlet flow, chamber pressure, susceptor speed, substrate temperature, etc.), so as to solve the problems of deposition rate and thin film uniformity in epitaxial growth.

[0005] At present, there is still a lack of research on the coupling mechanism of MOCVD multi-process parameters based on digital twin technology in the market. Summary of the invention

[0006] In order to overcome the problems mentioned in the background technology, the present invention provides a MOCVD equipment deposition method based on a digital twin model.

[0007] In order to achieve the above technical objectives, the technical solution adopted by the present invention is: A MOCVD equipment deposition method based on a digital twin model comprises the following steps: Step 1: According to the structure and size conditions of the actual MOCVD equipment, a digital twin geometric model of the MOCVD equipment is established, and the digital twin geometric model of the MOCVD equipment is discretized into a grid; Step 2: Obtain multiple different process parameter data collected by the industrial parameter sensor of the MOCVD equipment, input the process parameter data into the CFD computational fluid dynamics software as the numerical simulation boundary conditions of the digital twin geometric model, and build a simulated digital twin model; Step 3: CFD numerically simulates the digital twin geometry model through the process parameter data range to obtain the flow state data corresponding to different process parameters and the simulated growth rate under the flow state; Step 4: According to actual experiments, the actual growth rate of the MOCVD equipment under different process parameters is obtained, and the actual growth rate is compared with the simulated growth rate to correct the simulated growth rate; Step 5: Analyze the flow state data obtained in step 3 to obtain laminar flow and turbulent flow state diagrams under different process parameters, and then determine the stability process parameter value range of the MOCVD equipment in the laminar flow state and the corrected simulated growth rate corresponding to the stability process parameter value range, and form a visual industrial control platform; Step 6: Select the stability process parameters corresponding to the actual deposition requirements on the visual industrial control platform, and deposit the product in the MOCVD equipment.

[0008] To optimize the above technical solutions, the specific measures taken also include: In step 1, a 3D geometric model identical to the actual machine model is established using the 3D software PROE. The 3D geometric model is a digital twin geometric model of the MOCVD equipment.

[0009] In step 2, the process parameter data collected by the industrial parameter sensor of the MOCVD equipment include: the temperature T of the substrate base of the MOCVD equipment, the pressure P of the vacuum chamber, the base rotation speed ω, the gas flow rate Q of the metal organic source and the oxygen source, the gas inlet temperature, the inner wall temperature and the outer wall temperature of the gas outlet.

[0010] In step three, the method of numerically simulating the digital twin geometric model according to CFD is as follows: input the temperature T of the substrate base of the MOCVD equipment, the pressure P of the vacuum chamber, the base rotation speed ω, the gas flow rate Q of the metal organic source and the oxygen source, the gas inlet temperature, the inner wall temperature and the outer wall temperature of the gas outlet into the CFD, the gravitational acceleration adopts g=9.8m / s2, the inlet adopts the velocity inlet, the outlet is set to the pressure outlet, and the CFD is set to use the SIMPLE algorithm to solve the differential equation. The CFD outputs the flow state data and the simulated growth rate under the flow state.

[0011] In step three, when CFD performs numerical simulation on the digital twin geometric model, the simulation conditions are simplified so that the actual growth rate obtained in step four is different from the simulated growth rate.

[0012] The simplified simulation conditions are as follows: 1) Assume that the gas is an ideal gas with continuity and is treated as incompressible; 2) Ignore gas thermal radiation; 3) The base temperature is considered as a fixed temperature, and the outer wall surface can be considered as isothermal or adiabatic conditions; 4) Ignoring the energy loss caused by the relative motion between the walls and the gas, all walls in contact with the fluid and the reaction chamber adopt no-slip boundary conditions.

[0013] In step five, the laminar flow is: the fluids between flow layers do not mix with each other, and the turbulent flow is: the fluid particles move in a random pulsation form. The fluid particles between the flow layers mix and collide with each other, causing the movement elements of the fluid to pulsate randomly.

[0014] The present invention has the following beneficial effects: The present invention constructs a digital twin of the MOCVD chamber stability and establishes an intuitive and interactive visualization platform, which uses digital models and experiments to jointly guide the design and optimization of high-quality epitaxial materials, and provides a theoretical basis for the research and development of high-quality, high-efficiency and high-reliability thin-film epitaxial technology and high-end oxide semiconductor MOCVD equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic diagram of an MOCVD apparatus of the present invention; Figure 2 It is a schematic diagram of the digital twin geometric model of the MOCVD equipment; Figure 3 It is a diagram of laminar flow and turbulent flow states under different processes and conditions. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0017] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0018] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0019] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation and may indicate the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or units (units) is not limited to the listed steps or units, but may also include unlisted steps or units, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" / "several" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0020] A MOCVD equipment deposition method based on a digital twin model comprises the following steps: Step 1: According to the structure and size conditions of the actual MOCVD equipment, such as Figure 1As shown in the figure, a digital twin geometric model similar to that of the MOCVD equipment is established through the 3D software PROE. Figure 2 As shown, the digital twin geometric model of the MOCVD equipment is discretized into a grid; Step 2: Use the sensors inside the MOCVD chamber (specifically: flow sensor, temperature sensor, pressure sensor, speed sensor, corresponding to the four parameters of MOCVD, namely the temperature T of the substrate base of the MOCVD equipment, the pressure P of the vacuum chamber, the base speed ω, and the gas flow Q of the metal organic source and oxygen source) to transmit data with the MOCVD digital twin model, and act as a data extraction and integration module through serial communication, and act as an infrastructure connecting the physical world and cyberspace. Transmit data to the server to provide real-time data for the CFD computational fluid dynamics software for simulation calculations. At the same time, input the gas inlet temperature, gas outlet inner wall temperature and outer wall temperature into the CFD computational fluid dynamics software, set the range of the above data, and the CFD computational fluid dynamics software builds a simulated digital twin model; Step 3: Using the above process parameter data range, CFD performs numerical simulation on the digital twin geometric model. From the perspective of equation solving, combined with the actual flow conditions inside the reaction chamber, it is necessary to simplify the physical model. We make the following assumptions: 1) Assume that the gas is an ideal gas with continuity and is treated as incompressible; 2) Ignore gas thermal radiation; 3) The base temperature is considered as a fixed temperature, and the outer wall surface can be considered as isothermal or adiabatic conditions; 4) Ignoring the energy loss caused by the relative motion between the walls and the gas, all walls in contact with the fluid and the reaction chamber adopt no-slip boundary conditions.

[0021] The temperature T of the substrate base of the MOCVD equipment, the pressure P of the vacuum chamber, the rotation speed ω of the base, the gas flow rate Q of the metal organic source and the oxygen source, the gas inlet temperature, the inner wall temperature and the outer wall temperature of the gas outlet are input to the CFD. The gravity acceleration adopts g=9.8m / s2, the inlet adopts the velocity inlet, and the outlet is set as the pressure outlet. The CFD is set to use the SIMPLE algorithm to solve the differential equation. The CFD outputs the flow state data corresponding to different process parameters, as well as the simulated growth rate under the flow state.

[0022] Step 4: According to actual experiments, the actual growth rate of the MOCVD equipment under different process parameters is obtained, and the actual growth rate is compared with the simulated growth rate to correct the simulated growth rate; the correction method is to replace the simulated growth rate with the actual growth rate.

[0023] Step 5: Analyze the flow state data obtained in step 3 to obtain the laminar and turbulent state diagrams under different process parameters, and then determine the stability process parameter value range of the MOCVD equipment in the laminar state and the corrected simulated growth rate corresponding to the stability process parameter value range, and form a visual industrial control platform; Figure 3 As shown in the figure, except for the pressure P of the vacuum chamber and the rotation speed ω of the base, the other parameters are the same. The area represented by the red × is the turbulent area, the green circle area is the laminar area, and the critical point between the two is the blue line. In this flow state diagram, four points A, B, C, and D are selected. The visualization model of these four points is Figure 3 It is also shown in the figure. From these four visualization models, it can be seen that A and C are in turbulent state, and B and D are in laminar state. In B, when the airflow blows on the base, the airflow is flat on the surface of the base. When the substrate on the base is deposited, the thickness of the deposited layer is uniform. In D, when the airflow blows on the base, the airflow is wavy. The reason is that the rotational centrifugal force generated by the high-speed rotation of the base causes a large vortex inside the cavity. When the substrate on the base is deposited, the thickness of the deposited layer is uneven. A and C are not suitable for substrate deposition because they are in turbulent state.

[0024] Step 6: Select the stability process parameters corresponding to the actual deposition requirements on the visual industrial control platform, and deposit the product in the MOCVD equipment.

[0025] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A MOCVD equipment deposition method based on a digital twin model, characterized by: The following steps are involved: Step 1: According to the structure and size conditions of the actual MOCVD equipment, a digital twin geometric model of the MOCVD equipment is established, and the digital twin geometric model of the MOCVD equipment is discretized into a grid; Step 2: Obtain multiple different process parameter data collected by the industrial parameter sensor of the MOCVD equipment, input the process parameter data into the CFD computational fluid dynamics software as the numerical simulation boundary conditions of the digital twin geometric model, and build a simulated digital twin model; Step 3: CFD numerically simulates the digital twin geometry model through the process parameter data range to obtain the flow state data corresponding to different process parameters and the simulated growth rate under the flow state; Step 4: According to actual experiments, the actual growth rate of the MOCVD equipment under different process parameters is obtained, and the actual growth rate is compared with the simulated growth rate to correct the simulated growth rate; Step 5: Analyze the flow state data obtained in step 3 to obtain laminar flow and turbulent flow state diagrams under different process parameters, and then determine the stability process parameter value range of the MOCVD equipment in the laminar flow state and the corrected simulated growth rate corresponding to the stability process parameter value range, and form a visual industrial control platform; Step 6: Select the stability process parameters corresponding to the actual deposition requirements on the visual industrial control platform, and deposit the product in the MOCVD equipment.

2. The MOCVD equipment deposition method based on a digital twin model according to claim 1 is characterized in that: In step 1, a 3D geometric model identical to the actual machine model is established using the 3D software PROE. The 3D geometric model is a digital twin geometric model of the MOCVD equipment.

3. The MOCVD equipment deposition method based on a digital twin model according to claim 1 is characterized in that: In step 2, the process parameter data collected by the industrial parameter sensor of the MOCVD equipment include: the temperature T of the substrate base of the MOCVD equipment, the pressure P of the vacuum chamber, the base rotation speed ω, the gas flow rate Q of the metal organic source and the oxygen source, the gas inlet temperature, the inner wall temperature and the outer wall temperature of the gas outlet.

4. The MOCVD equipment deposition method based on a digital twin model according to claim 3 is characterized in that: In step three, the method of numerically simulating the digital twin geometric model according to CFD is as follows: input the temperature T of the substrate base of the MOCVD equipment, the pressure P of the vacuum chamber, the base rotation speed ω, the gas flow rate Q of the metal organic source and the oxygen source, the gas inlet temperature, the inner wall temperature and the outer wall temperature of the gas outlet into the CFD, the gravitational acceleration adopts g=9.8m / s2, the inlet adopts the velocity inlet, the outlet is set to the pressure outlet, and the CFD is set to use the SIMPLE algorithm to solve the differential equation. The CFD outputs the flow state data and the simulated growth rate under the flow state.

5. The MOCVD equipment deposition method based on a digital twin model according to claim 1 is characterized in that: In step three, when CFD performs numerical simulation on the digital twin geometric model, the simulation conditions are simplified so that the actual growth rate obtained in step four is different from the simulated growth rate.

6. The MOCVD equipment deposition method based on a digital twin model according to claim 5 is characterized in that: The simplified simulation conditions are as follows: 1) Assume that the gas is an ideal gas with continuity and is treated as incompressible; 2) Ignore gas thermal radiation; 3) The base temperature is considered as a fixed temperature, and the outer wall surface can be considered as isothermal or adiabatic conditions; 4) Ignoring the energy loss caused by the relative motion between the walls and the gas, all walls in contact with the fluid and the reaction chamber adopt no-slip boundary conditions.

7. The MOCVD equipment deposition method based on a digital twin model according to claim 1 is characterized in that: In step five, the laminar flow is: the fluids between flow layers do not mix with each other, and the turbulent flow is: the fluid particles move in a random pulsation form. The fluid particles between the flow layers mix and collide with each other, causing the movement elements of the fluid to pulsate randomly.

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