A vapor phase epitaxy apparatus

Abstract

The application belongs to the technical field of vapor phase epitaxy and relates to a vapor phase epitaxy device capable of being used for growing gallium nitride; the vapor phase epitaxy device comprises a control device and a growth device; the growth device comprises a reaction chamber, a raw material boat, a raw material supplementing chamber, a supplementing boat, an automatic adding device and a sensor; the raw material boat is arranged in the reaction chamber and is used for containing raw materials; the raw material supplementing chamber is communicated with the reaction chamber; the supplementing boat is arranged in the raw material supplementing chamber and is used for containing supplemented raw materials; the automatic adding device is arranged in the raw material supplementing chamber; the sensor is arranged in the reaction chamber and is coupled with the control device and is used for monitoring information of the raw materials; the control device obtains change information of the raw materials in the raw material boat based on the information of the raw materials, and controls the automatic adding device to supplement the raw materials to the raw material boat when the change information meets preset raw material supplementing conditions. The scheme solves the problems of the influence of raw material fluctuation on growth rate and growth concentration through the monitoring and automatic supplementing closed loop of the raw materials.

Description

Technical Field

[0001] This application relates to the field of vapor phase epitaxy technology, and more particularly to a vapor phase epitaxy apparatus. Background Technology

[0002] The core reaction for preparing gallium nitride (GaN) via hydride vapor phase epitaxy (HVPE) involves the reaction of metallic gallium (Ga) with hydrogen chloride (HCl) to generate gallium chloride (GaCl2) and hydrogen gas (H2), as shown in the equation: Ga + 2HCl → GaCl2 + H2↑. GaCl2 then reacts with ammonia to form GaN. During this process, the dynamic changes in the liquid level of metallic gallium within the raw material boat cause surface contraction and corner effects, resulting in discontinuous small areas on the liquid surface. This reduces the contact area between metallic gallium and hydrogen chloride gas, directly affecting the growth concentration of GaCl2, and consequently causing fluctuations in the GaN growth rate and concentration, thus impacting the uniformity and crystal quality of the GaN material.

[0003] Existing technologies address these issues by employing complex and cumbersome raw material boat structures or improving the distribution of reactive gases. However, these methods result in high equipment costs, uneven GaN growth concentration, and reduced uniformity of GaN materials. Furthermore, as the raw material liquid level decreases, the GaN growth concentration continuously decreases, leading to lower GaN crystal quality. Additionally, manual replenishment of raw materials can easily cause contamination and oxidation. Summary of the Invention

[0004] Therefore, the technical problem to be solved by this application is to overcome the problems of high equipment cost, uneven GaN growth concentration, and affecting the uniformity of GaN material when preparing GaN by changing the structure of the raw material boat or the distribution of the reactant gas in the prior art. Furthermore, as the raw material liquid level decreases, the GaN growth concentration continuously decreases, resulting in lower GaN crystal quality. At the same time, artificial replenishment of raw materials can easily cause raw material contamination and oxidation.

[0005] To address the aforementioned technical problems, this application provides a vapor phase epitaxy apparatus, comprising: a control device and a growth device, wherein the growth device includes:

[0006] Reaction chamber;

[0007] A raw material boat, located within the reaction chamber, is used to hold the raw materials;

[0008] A raw material replenishment chamber is connected to the reaction chamber;

[0009] A replenishment boat, located within the raw material replenishment chamber, is used to hold replenished raw materials;

[0010] An automatic feeding device is installed in the raw material replenishment chamber;

[0011] A sensor, disposed within the reaction chamber and coupled to the control device, is used to monitor information about the raw materials;

[0012] The control device is used to obtain information on changes in the raw materials in the raw material boat based on the information of the raw materials. When the information on changes meets the preset conditions for replenishing raw materials, the control device is used to control the automatic addition device to replenish the raw material boat. The information on changes includes changes in the liquid level of the raw materials or changes in the weight of the raw materials.

[0013] In this application, a raw material replenishment chamber connected to the reaction chamber is set up. Simultaneously, sensors monitor raw material information in real time. A control device then uses this information to obtain the changes in liquid level and weight of the raw material in the raw material boat. When the raw material in the boat is consumed during the reaction, the dynamic changes in liquid level lead to a decrease in the reaction area, resulting in a reduction in the growth concentration and growth rate of GaN. The control device then controls an automatic replenishment device in the raw material replenishment chamber to achieve automated replenishment of the raw material, realizing a dynamic balance of the raw material liquid level during the reaction process. This minimizes the impact of dynamic changes in the raw material liquid level on the growth rate and growth concentration, ensuring the uniformity and crystal quality of the GaN material. This approach eliminates the need for a complex raw material boat and gas pipeline design, reducing system costs. It also avoids the problems of raw material contamination and oxidation caused by manual addition. The closed-loop system of raw material monitoring and automatic replenishment solves the problem of growth rate and growth concentration being affected by raw material fluctuations within the raw material boat.

[0014] Preferably, the preset raw material replenishment condition is: the decrease in the liquid level of the raw material is greater than a first preset value or the decrease in the weight of the raw material is greater than a second preset value.

[0015] In this application, when the decrease in liquid level or weight of raw materials in the raw material boat exceeds a preset value, it indicates that the consumption of raw materials in the raw material boat is large, and it is necessary to use a control device to control the automatic addition device to replenish the raw materials in the raw material boat.

[0016] Preferably, the automatic adding device includes:

[0017] Transmission pipeline;

[0018] A conveying device, coupled to the control device and connected to the replenishment boat and the raw material boat via the transmission pipeline, is used to convey the raw materials in the replenishment boat to the raw material boat based on the control commands of the control device.

[0019] In this application, the automatic addition device uses a conveying device to add raw materials from the replenishment boat to the raw material boat through a transmission pipeline. Under the control command of the control device, the raw materials can be stably transported, avoiding the pollution and loss caused by frequent manual addition of raw materials.

[0020] Preferably, the vapor phase epitaxy apparatus further includes a baffle disposed between the reaction chamber and the raw material replenishment chamber;

[0021] The transmission pipeline includes a first transmission pipeline and a second transmission pipeline. The first transmission pipeline is connected to the replenishment boat; the second transmission pipeline passes through the baffle and is connected to the raw material boat.

[0022] Preferably, the vapor phase epitaxy apparatus further includes an airtight component, which is disposed at the contact point between the second conveying pipe and the baffle;

[0023] And / or, the baffle is made of quartz, alumina, or silicon carbide.

[0024] Preferably, the growth apparatus further includes an inert protective gas conduit that penetrates the side wall of the raw material replenishment chamber, for introducing inert gas into the raw material replenishment chamber to prevent oxidation of the raw material in the replenishment boat. In this application, by providing an inert protective gas conduit, the raw material replenishment chamber is kept constantly filled with inert gas, making the raw material less susceptible to oxidation.

[0025] Preferably, the sensor includes a liquid level monitoring sensor, which is disposed above the raw material boat and coupled to the control device, and the liquid level monitoring sensor includes:

[0026] A laser emitter is positioned above the raw material boat and is used to emit a first optical signal into the raw materials inside the raw material boat.

[0027] A laser receiver is positioned above the raw material boat to receive the second light signal reflected from the raw material inside the raw material boat.

[0028] A temperature detector is used to monitor the ambient temperature inside the raw material boat in real time.

[0029] The control device is used to determine the change in the liquid level of the raw material in the raw material boat based on the ambient temperature, the first optical signal, and the second optical signal.

[0030] In this application, a laser emitter emits a first light signal toward the surface of the raw material liquid, and a laser receiver receives a second light signal reflected from the surface of the raw material liquid. A control device obtains the liquid level of the raw material in the raw material boat based on the time difference between the first and second light signals, thereby determining the amount of change in the liquid level. Since the refractive index of the air in the raw material boat changes with temperature, thus altering the laser beam speed, a temperature detector is set up to monitor the ambient temperature in the raw material boat in real time. This allows the control device to determine the amount of change in the liquid level in the raw material boat under the current ambient temperature based on the ambient temperature, the first light signal, and the second light signal, avoiding the problem of inaccurate liquid level changes due to changes in ambient temperature.

[0031] Preferably, the growth apparatus further includes a bottom support structure disposed within the reaction chamber, the bottom support structure being used to support the raw material boat;

[0032] The sensor also includes a quality monitoring sensor, which is disposed in the bottom support structure. The quality monitoring sensor includes:

[0033] At least one force sensor is coupled to the control device;

[0034] A temperature-sensitive sensor is coupled to the control device;

[0035] The control device is used to determine the amount of weight change based on the information detected by the force sensor and the information detected by the temperature sensor.

[0036] Furthermore, the force sensor detects a first signal change caused by strain in the bottom support structure; the temperature sensor detects a second signal change caused by temperature change within the bottom support structure; and the control device determines the weight change based on the first and second signal changes.

[0037] In this application, a bottom support structure is provided at the bottom of the raw material boat, and a force sensor and a temperature sensor are installed in the bottom support structure. Since the bottom support structure will generate strain when the weight of the raw material in the raw material boat changes, the force sensor can detect the first signal change caused by the strain of the bottom support structure in real time. Furthermore, since the ambient temperature fluctuation will affect the measurement value of the force sensor, the temperature sensor is installed in the bottom support structure to detect the second signal change caused by the temperature change of the bottom support structure. This allows the control device to obtain a more accurate weight change of the raw material based on the first and second signal changes, eliminating the influence of temperature fluctuation on the measurement result of the weight change.

[0038] Preferably, a nano-coating is provided on the bottom and sidewalls of the raw material boat, the nano-coating being used to prevent the raw material inside the raw material boat from wetting the bottom and sidewalls of the raw material boat.

[0039] In this application, by providing an anti-adhesion nano-coating on the sidewalls and bottom of the raw material boat, the measurement deviation of liquid level change caused by the raw material wetting the raw material boat can be prevented, thereby improving the measurement accuracy of liquid level change.

[0040] Preferably, the inner wall of the reaction chamber is provided with a first heat insulation layer, which is coupled to the control device to keep the raw material in the raw material boat in a liquid state;

[0041] And / or, the inner wall of the raw material replenishment chamber is provided with a second insulation layer, which is coupled to the control device to keep the raw material in the replenishment boat in a liquid state.

[0042] In this application, when the melting point of the raw material (such as metallic gallium) is low, large temperature fluctuations will cause it to crystallize and solidify. Therefore, this application provides a heat insulation layer on the inner wall of both the reaction chamber and the raw material replenishment chamber. The heat insulation layer is controlled by a control device to maintain the temperature in the reaction chamber and the raw material replenishment chamber above the melting point of the raw material, so that the entire reaction and the raw material replenishment process are carried out under constant temperature conditions, thereby keeping the raw material in a liquid state for a long time.

[0043] The vapor phase epitaxy apparatus provided in this application has the following beneficial effects:

[0044] The vapor phase epitaxy apparatus provided in this application includes a control device and a growth device. The growth device includes a reaction chamber, a raw material boat, a raw material replenishment chamber, a replenishment boat, an automatic addition device, and a sensor. The raw material boat is disposed in the reaction chamber and is used to hold the raw material. The raw material replenishment chamber is connected to the reaction chamber. The replenishment boat is disposed in the raw material replenishment chamber and is used to hold and replenish the raw material. The automatic addition device is disposed in the raw material replenishment chamber. The sensor is disposed in the reaction chamber and coupled to the control device for monitoring the information of the raw material. The control device determines the change information of the raw material in the raw material boat based on the information monitored by the sensor, and controls the automatic addition device to replenish the raw material boat when the change information meets the preset raw material replenishment conditions. The change information includes the change in the liquid level of the raw material or the change in the weight of the raw material. This application establishes a raw material replenishment chamber connected to the reaction chamber. Sensors monitor raw material information in real time, and a control device determines the changes in liquid level or weight of the raw material in the raw material boat. When the raw material in the boat is consumed during the reaction, the dynamic changes in liquid level lead to a decrease in the reaction area, resulting in a reduction in the growth concentration and growth rate of GaN. The control device then automatically replenishes the raw material using an automatic addition device within the raw material replenishment chamber, achieving dynamic balance of the raw material liquid level during the reaction process. This minimizes the impact of dynamic changes in the raw material liquid level on the growth rate and growth concentration, ensuring the uniformity and crystal quality of the GaN material. This approach eliminates the need for a complex raw material boat and gas pipeline design, reducing system costs, and avoids the problems of contamination and oxidation caused by manual addition of raw materials. The closed-loop system of raw material monitoring and automatic replenishment solves the problem of growth rate and growth concentration being affected by fluctuations in the raw material within the boat. Attached Figure Description

[0045] To make the content of this application easier to understand, the following detailed description is provided based on specific embodiments and accompanying drawings, wherein:

[0046] Figure 1 A schematic diagram of the vapor phase epitaxy apparatus provided in this application;

[0047] Figure 2 This is a schematic diagram of the structure of a liquid level monitoring sensor provided in this application;

[0048] Figure 3 This application provides a schematic diagram of the structure of a quality monitoring sensor.

[0049] Explanation of reference numerals in the accompanying drawings: 1. Control device; 2. Growth device; 21. Reaction chamber; 22. Raw material boat; 221. Air inlet pipe; 222. Bottom support structure; 23. Raw material replenishment chamber; 24. Replenishment boat; 25. Automatic addition device; 251. Transfer pipe; U1. First conveying pipe; U2. Second conveying pipe; 252. Conveying device; 26. Sensor; 261. Liquid level monitoring sensor; U3. Laser emitter; U4. Laser receiver; U5. Temperature detector; 262. Quality monitoring sensor; U6. Force sensor; U7. Temperature sensor; 27. First insulation layer; 28. Second insulation layer; 29. ​​Inert protective gas pipe; 30. Baffle. Detailed Implementation

[0050] The present application will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present application, but the embodiments are not intended to limit the present application.

[0051] Please see Figure 1 , Figure 1 The diagram shown is a schematic diagram of the vapor phase epitaxy apparatus provided in this application. The vapor phase epitaxy apparatus includes a control device 1 and a growth device 2.

[0052] The growth apparatus 2 includes a reaction chamber 21, a raw material boat 22, a raw material replenishment chamber 23, a replenishment boat 24, an automatic addition device 25, and a sensor 26.

[0053] The raw material boat 22 is located inside the reaction chamber 21. The raw material boat 22 is used to hold raw materials, which can be metallic gallium or metallic aluminum.

[0054] The raw material replenishment chamber 23 is connected to the reaction chamber 21.

[0055] The replenishment boat 24 is located inside the raw material replenishment chamber 23.

[0056] The automatic addition device 25 is installed in the raw material replenishment chamber 23.

[0057] Sensor 26 is located inside reaction chamber 21 and coupled to control device 1 to monitor information about the raw materials, such as the liquid level or weight of the raw materials.

[0058] The control device 1 is used to obtain the change information of the raw materials in the raw material boat 22 based on the information of the raw materials. When the change information meets the preset raw material replenishment conditions, the control device 25 is used to replenish the raw materials in the raw material boat 22. The change information includes the change in the liquid level of the raw materials or the change in the weight of the raw materials.

[0059] This embodiment includes a raw material replenishment chamber 23 connected to the reaction chamber 21. Sensor 26 monitors the information within the raw material boat 22 in real time, allowing the control device 1 to determine the change in liquid level or weight of the raw material within the boat based on the information monitored by sensor 26. When the raw material in the boat 22 is consumed during the reaction, the dynamic change in liquid level leads to a decrease in the reaction area, resulting in a reduction in the growth concentration and growth rate of GaN. The control device 1 then controls the automatic addition device 25 within the raw material replenishment chamber 23 to automatically replenish the raw material, achieving dynamic balance of the raw material liquid level during the reaction process. This minimizes the impact of dynamic changes in the raw material liquid level on the growth rate and growth concentration, ensuring the uniformity and crystal quality of the GaN material. This approach eliminates the need for a complex raw material boat and gas pipeline design, reducing system costs, and avoids the problems of contamination and oxidation caused by manual addition of raw materials. The closed-loop system of raw material monitoring and automatic replenishment solves the problem of growth rate and growth concentration being affected by fluctuations in the raw material within the boat 22.

[0060] Furthermore, the preset raw material replenishment conditions are that the decrease in raw material level is greater than a first preset value or the decrease in raw material weight is greater than a second preset value. For example, when the raw material level in the raw material boat 22 is lower than 10 mm, or the decrease in raw material weight is greater than 0.3 kg, the automatic addition device 25 can be controlled to replenish the raw material boat 22 at a rate of 0.1 L / min.

[0061] Furthermore, a nano-coating (not shown in the figure) is provided on the bottom and sidewalls of the raw material boat 22. The nano-coating is used to prevent the raw material inside the raw material boat 22 from wetting the bottom and sidewalls of the raw material boat 22.

[0062] By applying an anti-adhesion nano-coating to the sidewalls and bottom of the raw material boat 22, the measurement deviation of liquid level change caused by the raw material wetting the raw material boat 22 can be prevented, thereby improving the measurement accuracy of liquid level change.

[0063] Furthermore, the inner wall of the reaction chamber 21 is provided with a first insulation layer 27, which is coupled to the control device 1. The first insulation layer 27 is used to keep the raw material in the raw material boat 22 in a liquid state.

[0064] Furthermore, the inner wall of the raw material replenishment chamber 23 is provided with a second insulation layer 28, which is coupled to the control device 1. The second insulation layer 28 is used to keep the raw material in the replenishment boat 24 in a liquid state.

[0065] Specifically, the first insulation layer 27 and the second insulation layer 28 each include a temperature control mechanism and a heating device (e.g., a heating element) (not shown in the figure). The temperature control mechanism is coupled to the control device 1. After receiving heating information from the control device 1, the temperature control mechanism heats the heating element, thereby making the temperature in the reaction chamber 21 and the raw material replenishment chamber 23 higher than the melting point of the raw material, thus keeping the raw material in the raw material boat 22 in a liquid state. Alternatively, the first insulation layer 27 and the second insulation layer 28 may also include a cooling device. After receiving cooling information from the control device 1, the temperature control mechanism cools the reaction chamber 21 to keep the raw material in the raw material boat 22 in a liquid state.

[0066] Since the raw materials have low melting points, large temperature fluctuations can cause them to crystallize and solidify. Therefore, by providing insulation layers (i.e., the first insulation layer 27 and the second insulation layer 28) on the inner walls of both the reaction chamber 21 and the raw material replenishment chamber 23, the temperature inside the reaction chamber 21 and the raw material replenishment chamber 23 can be maintained above the melting point of the raw materials. This ensures that the entire reaction and the raw material replenishment process are carried out under constant temperature conditions, thereby keeping the raw materials in a stable liquid state for a long time.

[0067] Understandably, in other embodiments, the first insulation layer 27 and the second insulation layer 28 may not be coupled to the control device 1, and they may be made of insulation material.

[0068] Furthermore, such as Figure 1 As shown, the automatic adding device 25 includes a transmission pipe 251 and a conveying device 252.

[0069] The conveying device 252 is coupled to the control device 1 and is connected to the replenishment boat 24 and the raw material boat 22 through the transmission pipe 251. The conveying device 252 is used to convey the raw materials in the replenishment boat 24 to the raw material boat 22 based on the control command of the control device 1.

[0070] Specifically, the transmission pipe 251 is a fluororubber pipe or a silicone rubber pipe. This is because some raw materials (such as metallic gallium) are prone to alloying reactions with various metals, affecting the lifespan and strength of the metals. Therefore, the material of the transmission pipe 251 is a high-temperature resistant composite material such as fluororubber or silicone rubber. Among them, the upper limit of the high-temperature resistance of fluororubber is 300℃, and the upper limit of the high-temperature resistance of silicone rubber is 350℃. This can avoid alloying reactions with raw materials and also prevent the transmission pipe 251 from aging due to high temperatures.

[0071] The conveying device 252 can be a piezoelectric peristaltic pump, an electromagnetic induction pump, or a pneumatic diaphragm pump. Among them, the piezoelectric peristaltic pump is suitable for scenarios requiring precise addition of small amounts of raw materials, enabling high-precision replenishment of raw material liquid; the electromagnetic induction pump is suitable for high-flow continuous production, enabling rapid replenishment of raw material liquid when it is consumed quickly; and the pneumatic diaphragm pump is suitable for medium-flow intermittent operation, and can be used when the reaction rate is moderate.

[0072] Furthermore, such as Figure 1 As shown, the vapor phase epitaxy apparatus also includes a baffle 29 disposed between the reaction chamber 21 and the raw material replenishment chamber 23. Optionally, the baffle 29 can be made of a stable material with high temperature resistance and corrosion resistance, such as quartz, alumina, or silicon carbide.

[0073] Furthermore, the transmission pipeline 251 includes a first transmission pipeline U1 and a second transmission pipeline U2. The first transmission pipeline U1 is connected to the replenishment boat 24; the second transmission pipeline U2 passes through the baffle 29 and is connected to the raw material boat 22.

[0074] Furthermore, the vapor phase epitaxy apparatus also includes a gas-tight component (not shown in the figure), which is disposed at the contact point between the second delivery pipe U2 and the baffle 29. Optionally, the gas-tight component is preferably made of acid-resistant and high-temperature-resistant materials such as silicone rubber and fluororubber.

[0075] Furthermore, such as Figure 1 As shown, the growth apparatus 2 also includes an inert protective gas pipeline 30, which runs through the side wall of the raw material replenishment chamber 23 and is used to introduce inert gas into the raw material replenishment chamber 23 to prevent the raw materials in the replenishment boat 24 from oxidizing.

[0076] Furthermore, sensor 26 includes a liquid level monitoring sensor 261, which is disposed above the raw material boat 22 and coupled to the control device 1. For example... Figure 1 As shown, the liquid level monitoring sensor 261 can be installed between the air inlet pipes 221 above the raw material boat 22. The air inlet pipes 221 are used to introduce reaction gases, such as HCl. Optionally, the liquid level monitoring sensor 261 can be a laser rangefinder, an ultrasonic level gauge, or a capacitive level gauge.

[0077] Preferably, in one embodiment of this application, the liquid level monitoring sensor 261 is a laser rangefinder sensor, such as... Figure 2 As shown, the liquid level monitoring sensor 261 includes a laser emitter U3, a laser receiver U4, and a temperature detector U5.

[0078] Laser emitter U3 is positioned above raw material boat 22 and is used to emit a first optical signal into the raw material inside the raw material boat 22. For example, the first optical signal is a near-infrared pulsed light signal with a wavelength of 905 nm.

[0079] The laser receiver U4 is positioned above the raw material boat 22 and is used to receive the second light signal reflected by the raw material inside the raw material boat 22.

[0080] Temperature detector U5 is used to detect the ambient temperature inside the raw material boat 22 in real time, so that the control device 1 can determine the change in the liquid level of the raw material inside the raw material boat 22 based on the ambient temperature, the first light signal and the second light signal.

[0081] Specifically, the control device 1 determines the liquid level change in the raw material boat 22 based on the time difference between the laser transmitter U3 emitting the first optical signal and the laser receiver U4 receiving the second optical signal. Since the air refractive index in the raw material boat 22 changes with temperature, thus altering the laser speed, a temperature detector U5 is set up to detect the ambient temperature in the raw material boat 22 in real time. This allows the control device 1 to detect the liquid level change in the raw material boat 22 in real time under the current ambient temperature, avoiding the problem of inaccurate liquid level change due to changes in ambient temperature.

[0082] Specifically, the steps for control device 1 to detect the change in liquid level in raw material boat 22 in real time under the current ambient temperature are as follows:

[0083] Step 1: Calculate the air refractive index based on the ambient temperature detected by temperature detector U5.

[0084] The formula for calculating the refractive index of air at the current ambient temperature is:

[0085]

[0086] in, Indicates the refractive index of air; This indicates the ambient temperature inside the raw material boat 22 (i.e., the ambient temperature detected by temperature detector U5). This indicates a reference temperature, such as 20℃.

[0087] Step 2: Calculate the laser speed at the current ambient temperature.

[0088] The formula for calculating the laser speed at the current ambient temperature is:

[0089]

[0090] in, This represents the laser speed at the current ambient temperature. It represents the speed of light in a vacuum.

[0091] Step 3: Based on the laser speed and time difference (i.e., the time difference between the first and second light signals) at the current ambient temperature, calculate the vertical distance from the liquid level monitoring sensor 261 to the raw material liquid surface.

[0092] The formula for calculating the vertical distance from the liquid level monitoring sensor 261 to the raw material liquid surface is as follows:

[0093]

[0094] in, This indicates the vertical distance between the liquid surface and the liquid level monitoring sensor 261; Indicates time difference.

[0095] Step 4: Based on the vertical distance from the liquid level monitoring sensor 261 to the raw material liquid surface and the vertical distance between the liquid level monitoring sensor 261 and the bottom of the raw material boat 22, obtain the raw material liquid level in the raw material boat 22 at the current ambient temperature.

[0096] The formula for calculating the raw material level in raw material boat 22 at the current ambient temperature is:

[0097]

[0098] in, Indicates the raw material liquid level; This indicates the vertical distance between the liquid level monitoring sensor 261 and the bottom of the raw material boat 22.

[0099] Due to factors such as raw material flow, bubbles, and vibration within the raw material boat 22, the liquid level will experience random fluctuations. These fluctuations will affect the accuracy of liquid level measurement. Therefore, multiple liquid level monitoring sensors 261 can be set up to measure the liquid level at different locations on the liquid surface. By weighting and averaging the results of multiple measurements, the influence of random noise on the measurement results can be suppressed, and the detected changes in the liquid level of the raw material can be corrected.

[0100] Optionally, the number of liquid level monitoring sensors 261 can be 2, 3, 4 or other, and this application does not limit it. When the number of liquid level monitoring sensors 261 is N, the setting interval of adjacent liquid level monitoring sensors 261 can be 360° / N.

[0101] Furthermore, such as Figure 1 As shown, the growth apparatus 2 also includes a bottom support structure 222, which is disposed in the reaction chamber 21 and is used to support the raw material boat 22.

[0102] Furthermore, such as Figure 3 As shown, sensor 26 also includes a quality monitoring sensor 262, which is disposed in the bottom support structure 222. The quality monitoring sensor 262 includes at least one force sensor U6 and a temperature sensor U7.

[0103] Force sensor U6 is used to detect the first signal change caused by strain on the bottom support structure 222 in real time. Temperature sensor U7 is used to detect the second signal change caused by temperature change on the bottom support structure 222 in real time. Control device 1 is used to determine the weight change based on the first and second signal changes.

[0104] Specifically, the first signal change and the second signal change can be either an optical signal change or an electrical signal change.

[0105] Optionally, the force sensor U6 can be a fiber optic strain sensor, a piezoelectric resonant sensor, or a strain gauge pressure sensor. Specifically, when the force sensor U6 is a fiber optic strain sensor, it can detect the Bragg wavelength shift caused by strain in the bottom support structure 222; when the force sensor U6 is a voltage resonant sensor, it can detect the frequency shift caused by strain in the bottom support structure 222; and when the force sensor U6 is a strain gauge pressure sensor, it can detect the voltage shift caused by strain in the bottom support structure 222.

[0106] Optionally, the temperature sensor U7 is a temperature sensor or a temperature grating. When the temperature sensor U7 is a temperature sensor, it can detect frequency or voltage shifts caused by temperature fluctuations; when the temperature sensor U7 is a temperature sensor, it can detect Bragg wavelength shifts caused by temperature fluctuations.

[0107] Since temperature fluctuations in the bottom support structure 222 can also cause strain, resulting in changes in the detection value of the force sensor U6, this application uses a temperature sensor U7 to detect the signal change in the bottom support structure 222 caused by temperature, thereby correcting the measurement value of the force sensor U6 and retaining only the signal change caused by the strain of the bottom support structure 222 due to the weight change of the raw material. This eliminates the influence of temperature fluctuations on the measurement results of the weight change of the raw material.

[0108] Specifically, when the force sensor U6 is an optical fiber strain sensor and the temperature sensor U7 is a temperature grating, the detected values ​​of both sensors are Bragg wavelength offsets.

[0109] Specifically, the Bragg wavelength offset measured by the force sensor U6 Strain of bottom support structure 222 The relationship can be represented as:

[0110]

[0111] in, Indicates the Bragg wavelength; This represents the effective photoelastic coefficient.

[0112] The Bragg wavelength shift caused by temperature fluctuations, as measured by the temperature-sensitive sensor U7, is as follows:

[0113]

[0114] in, This indicates the coefficient of thermal expansion of the bottom support structure 222 (e.g., the coefficient of thermal expansion of stainless steel is...). ); Indicates the thermo-optic coefficient of the optical fiber. , This represents the change in temperature.

[0115] Furthermore, the step of the control device 1 determining the weight change of the raw material based on the first signal change and the second signal change is as follows:

[0116] Step 1: Based on the change in the second signal obtained by the temperature sensor U7 (i.e., ( The change in the first signal measured by the force sensor U6 ( The wavelength shift caused by the change in raw material weight is obtained by making corrections. for:

[0117]

[0118] Step 2: Based on the wavelength shift caused by changes in raw material weight Calculate the strain of the bottom support structure 222 caused by the change in the weight of the raw materials.

[0119] The strain of the bottom support structure 222 is caused only by the change in the weight of the raw material. As shown below:

[0120]

[0121] Step 3: Calculate the amount of weight change of the raw material based on the strain of the bottom support structure 222 caused by the weight change of the raw material.

[0122] Change in weight of raw materials With strain The relationship between them is as follows:

[0123]

[0124] in, This indicates the force applied to the bottom support structure 222. , Represents gravitational acceleration; Indicates the length of the lever arm; This indicates the elastic modulus of the bottom support structure 222 (for example, the elastic modulus of stainless steel is 200 GPa). Represents the moment of inertia of the cross section; This represents the cross-sectional area of ​​the bottom support structure 222.

[0125] Therefore, the weight change of the raw materials in the raw material boat 22 for:

[0126]

[0127] Optionally, the number of force sensors U6 can be 6, 8, 10, or other. When the number of force sensors U6 is large, multiple force sensors U6 can be arranged in a ring in the bottom support structure 222; for example, Figure 3 The diagram shows the arrangement of eight force sensors U6. By arranging multiple force sensors U6 in a ring in the bottom support structure 222, strain can be detected at different positions of the bottom support structure 222, thereby more accurately measuring the weight change of the raw material in the raw material boat 22.

[0128] This application first implements modular real-time monitoring of both the liquid level and mass of the raw materials. By combining changes in liquid level and mass with traditional equipment, a new raw material replenishment chamber and an automatic addition device are added for storing and replenishing raw materials. This closed-loop solution addresses the impact of raw material fluctuations within the raw material boat on the subsequent growth rate. Simultaneously, by incorporating changes in process parameters during the growth process, the liquid level, mass, and flow rate of the raw materials can be adjusted in real time to maintain a relatively stable state within the raw material boat, thereby achieving a dynamic equilibrium with the reactant gases.

[0129] Furthermore, this application utilizes an automatic replenishment device to achieve automated raw material replenishment, which avoids pollution and loss caused by frequent manual addition of raw materials and also prevents the raw materials inside the chamber from oxidizing, maintaining a stable liquid state over a long period. Moreover, the entire raw material replenishment and transportation process is carried out at a constant temperature, ensuring that the entire process of automatically adding raw materials from the raw material replenishment chamber to the raw material boat is a non-contact, temperature-controlled transfer.

[0130] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A vapor phase epitaxy apparatus, characterized in that, include: A control device and a growth device, wherein the growth device includes: Reaction chamber; A raw material boat, located within the reaction chamber, is used to hold the raw materials; A raw material replenishment chamber is connected to the reaction chamber; A replenishment boat, located within the raw material replenishment chamber, is used to hold replenished raw materials; An automatic feeding device is installed in the raw material replenishment chamber; A sensor, disposed within the reaction chamber and coupled to the control device, is used to monitor information about the raw materials; The control device is used to obtain information on changes in the raw materials in the raw material boat based on the information of the raw materials. When the information on changes meets the preset conditions for replenishing raw materials, the control device controls the automatic addition device to replenish the raw material boat. The information on changes includes changes in the liquid level of the raw materials or changes in the weight of the raw materials.

2. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The preset raw material replenishment conditions are: the decrease in the liquid level of the raw material is greater than the first preset value or the decrease in the weight of the raw material is greater than the second preset value.

3. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The automatic adding device includes: Transmission pipeline; A conveying device, coupled to the control device and connected to the replenishment boat and the raw material boat via the transmission pipeline, is used to convey the raw materials in the replenishment boat to the raw material boat based on the control commands of the control device.

4. The vapor phase epitaxy apparatus according to claim 3, characterized in that, The vapor phase epitaxy apparatus further includes a baffle disposed between the reaction chamber and the raw material replenishment chamber; The transmission pipeline includes a first transmission pipeline and a second transmission pipeline. The first transmission pipeline is connected to the replenishment boat; the second transmission pipeline passes through the baffle and is connected to the raw material boat.

5. The vapor phase epitaxy apparatus according to claim 4, characterized in that, The vapor phase epitaxy apparatus further includes an airtight component, which is disposed at the contact point between the second delivery pipe and the baffle. And / or, the baffle is made of quartz, alumina, or silicon carbide.

6. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The growth apparatus also includes an inert protective gas pipeline that runs through the side wall of the raw material replenishment chamber and is used to introduce inert gas into the raw material replenishment chamber to prevent oxidation of the raw materials in the replenishment boat.

7. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The sensor includes a liquid level monitoring sensor, which is disposed above the raw material boat and coupled to the control device. The liquid level monitoring sensor includes: A laser emitter is positioned above the raw material boat and is used to emit a first optical signal into the raw materials inside the raw material boat. A laser receiver is positioned above the raw material boat to receive the second light signal reflected from the raw material inside the raw material boat. A temperature detector is used to monitor the ambient temperature inside the raw material boat in real time. The control device is used to determine the change in the liquid level of the raw material in the raw material boat based on the ambient temperature, the first optical signal, and the second optical signal.

8. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The growth apparatus further includes a bottom support structure disposed within the reaction chamber, the bottom support structure being used to support the raw material boat; The sensor also includes a quality monitoring sensor, which is disposed in the bottom support structure. The quality monitoring sensor includes: At least one force sensor is coupled to the control device; A temperature-sensitive sensor is coupled to the control device; The control device is used to determine the amount of weight change based on the information detected by the force sensor and the information detected by the temperature sensor.

9. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The bottom and sidewalls of the raw material boat are provided with a nano-coating, which is used to prevent the raw material inside the raw material boat from wetting the bottom and sidewalls of the raw material boat.

10. The vapor phase epitaxy apparatus according to claim 1, characterized in that, The inner wall of the reaction chamber is provided with a first heat insulation layer, which is coupled to the control device and is used to keep the raw material in the raw material boat in a liquid state. And / or, the inner wall of the raw material replenishment chamber is provided with a second insulation layer, which is coupled to the control device to keep the raw material in the replenishment boat in a liquid state.

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