Standby energy-saving structure system and energy-saving method thereof

Abstract

The invention belongs to the technical field of semiconductor wafer manufacturing, and particularly relates to a standby energy-saving structure system and an energy-saving method thereof. The invention provides a standby energy-saving structure system which comprises a reaction cavity, a base, a heater, a control system, a gas inlet and a multi-layer coaxial nozzle, and the multi-layer coaxial nozzle comprises a first gas channel used for conveying a metal organic source, an isolation channel, a second gas channel used for conveying a hydride source, a heating resistance wire and a phase change heat storage layer. According to the structure system, the splitting decomposition efficiency of NH3 can be improved by utilizing heat energy in a standby stage, and the splitting decomposition efficiency is quickly released when production is recovered, so that the energy consumption is reduced, the preheating time is shortened, the production efficiency is improved, a heat flow path is naturally switched only by putting in / moving out a wafer, and the structure is simplified and reliable.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor wafer manufacturing technology, and particularly relates to a standby energy-saving structure system and its energy-saving method. Background Technology

[0002] In the semiconductor wafer manufacturing industry, metal-organic chemical vapor deposition (MOCVD) is an important thin film growth technology, mainly used to grow compound semiconductor thin films such as gallium nitride and gallium arsenide. MOCVD equipment delivers group III metal-organic compounds (such as trimethylgallium™Ga) and group V hydrides (such as ammonia NH3) to the heated substrate surface, where a chemical reaction occurs at high temperature, epitaxially growing high-quality crystalline thin films.

[0003] In the epitaxial growth of GaN-based materials, NH3 serves as the nitrogen source, and its decomposition efficiency directly affects the growth rate and crystal quality of GaN. However, the decomposition reaction of NH3 requires a high-temperature environment to proceed effectively. In existing technologies, NH3 is usually introduced directly into the reaction chamber at room temperature. Due to the short residence time of NH3 in the reaction chamber, the decomposition rate is only below 30%. Directly increasing the overall temperature of the reaction chamber or extending the gas residence time would increase energy consumption, reduce production efficiency, and affect production capacity.

[0004] Meanwhile, MOCVD equipment requires frequent wafer loading and unloading operations during the production process. During wafer changeover, in order to conserve raw material gases, it is usually necessary to stop the supply of reaction gases and lower the temperature of the reaction chamber. After the new wafer is loaded, the temperature is then raised back to the growth temperature. This frequent heating and cooling operation with huge temperature differences is not only time-consuming but also consumes a lot of energy.

[0005] Therefore, the existing technology has the following shortcomings, which are the technical problems that this invention aims to solve: to effectively utilize existing energy sources to improve the cracking rate of NH3 while avoiding increased energy consumption.

[0006] Therefore, in summary, it is necessary to develop a new type of energy-saving MOCVD mechanism system to solve this problem. Summary of the Invention

[0007] This invention provides a standby energy-saving structural system, which includes a reaction chamber, a base, a heater, a control system, a gas inlet, and a multi-layer coaxial nozzle. The multi-layer coaxial nozzle includes a first gas channel for conveying a metal-organic source, an isolation channel, a second gas channel for conveying a hydride source, a heating resistance wire, and a phase change heat storage layer. This allows the structural system to utilize the heat energy during standby to improve the cracking efficiency of NH3 and release it rapidly when production resumes, thereby reducing energy consumption, shortening preheating time, and improving production efficiency. Furthermore, the heat flow path can be naturally switched simply by placing / removing the wafer, resulting in a simplified and reliable structure.

[0008] Therefore, the present invention overcomes the shortcomings of the prior art and provides the following technical solution: This invention provides a standby energy-saving structure system, including a reaction chamber, a base disposed within the reaction chamber for supporting a wafer, a heater disposed below the base, a gas inlet disposed at the top of the reaction chamber, a multi-layer coaxial nozzle disposed at the gas inlet and facing the wafer, and a control system; the multi-layer coaxial nozzle includes a first gas channel disposed at the center for delivering a metal-organic source, an isolation channel disposed outside the first gas channel, a second gas channel disposed outside the isolation channel for delivering a hydride source, a phase change heat storage layer disposed outside the second gas channel, and a heating resistance wire wound on the inner wall of the outer layer of the second gas channel.

[0009] A further preferred technical solution is that: TMGa is introduced into the first gas channel, NH3 is introduced into the second gas channel, and the phase change temperature of the phase change heat storage layer is 550℃-650℃.

[0010] A further preferred technical solution includes a recovery device; the recovery device includes an exhaust port located at the bottom of the reaction chamber, a waste gas pipe connected to the exhaust port, a heat exchanger located on the waste gas pipe, and a hydride source gas pipe connected to the heat exchanger and leading to the gas inlet.

[0011] A further preferred technical solution is that the multi-layer coaxial nozzle further includes a baffle plate disposed within the second gas channel and extending to the nozzle at its bottom end.

[0012] A further preferred technical solution is that the phase change heat storage layer includes an encapsulation shell disposed outside the second gas channel, and an Al-Si eutectic alloy and an inert gas disposed inside the encapsulation shell.

[0013] A further preferred technical solution is that the multi-layer coaxial nozzle further includes a distribution chamber disposed at the gas inlet and connected to the first gas channel, the isolation channel, and the second gas channel.

[0014] A further preferred technical solution is that the outlet end of the multi-layer coaxial nozzle is set in a conical shape, and an extension section is provided at the lower end.

[0015] This invention provides an energy-saving method for the standby energy-saving structure system described in the above technical solution, comprising the following steps: Power-on preheating step: loading the wafer onto the substrate, turning on the heater to heat the substrate, and turning on the heating resistance wire to preheat the second gas channel; Epitaxial growth step: when the substrate reaches the growth temperature, supplying TMGa to the first gas channel, supplying NH3 to the second gas channel, and supplying N2 to the isolation channel, so that NH3 is preheated in the nozzle and mixed with TMGa to perform GaN thin film epitaxial growth; Standby energy-saving step: when the wafer is removed from the substrate... Then, the supply to the first gas channel and the second gas channel is stopped, while the isolation channel retains a trace supply of N2. The heating power of the heater is reduced from the growth power to the heat preservation power. The thermal radiation of the base is radiated to the phase change heat storage layer. The phase change heat storage material in the phase change heat storage layer melts, absorbs heat, and stores thermal energy. Rapid recovery step: When the wafer is newly loaded onto the base, the heating power of the heater is restored to the growth power, and the supply to the first gas channel and the second gas channel is restored at the same time. The phase change heat storage layer solidifies, releases heat, and preheats the second gas channel.

[0016] A further preferred technical solution includes the following steps: waste heat recovery step: the waste gas in the reaction chamber enters the waste gas pipeline through the exhaust port, and exchanges heat with the NH3 to be supplied when it flows through the heat exchanger. The waste heat of the waste gas is used to preheat the NH3 to be supplied. The preheated NH3 is then introduced to the gas inlet through the hydride source gas pipe.

[0017] A further preferred technical solution is that, in the epitaxial growth step, NH3 is preheated to 550℃-650℃ inside the nozzle before being sprayed out.

[0018] The beneficial effects of this invention are at least as follows: 1. It improves the NH3 cracking efficiency by preheating NH3 to 550-650℃ through a preheating tube, extending the residence time of NH3 in the high-temperature zone and reducing raw material waste; 2. It uses a phase change heat storage layer to rapidly release heat in recovery mode, which not only heats NH3 but also shortens the heating time in the cavity, further reducing energy consumption. Moreover, the temperature control of the phase change heat storage layer is very stable, effectively avoiding overheating / overcooling; 3. It utilizes waste gas for heat recovery, reducing the energy consumption of electric heating; 4. The second gas channel can be switched to a circulation channel when closed, allowing cleaning to be performed without stopping the machine. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structural system of the present invention; Figure 2 This is a front cross-sectional view of the multi-layer coaxial nozzle of the present invention; Figure 3 This is a top cross-sectional view of the multi-layer coaxial nozzle of the present invention.

[0021] The meanings of the various reference numerals in the figure are as follows: wafer a; 1. Reaction chamber; 2. Base; 3. Heater; 4. Gas inlet; 5. Multi-layer coaxial nozzle; 6. Recovery device; First gas passage 51, isolation passage 52, second gas passage 53, phase change heat storage layer 54, heating resistance wire 55, partition 56, distribution chamber 57, extension section 58, exhaust port 61, waste gas pipe 62, heat exchanger 63, hydride source gas pipe 64. Package 541. Detailed Implementation

[0022] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention.

[0023] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc., mentioned or possibly mentioned in this specification are defined relative to the structure shown in the accompanying drawings. The terms "inner" and "outer" refer to the direction toward or away from the geometric center of a specific component, respectively. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive terms.

[0024] This invention provides a standby energy-saving structure system, including a reaction chamber 1, a base 2 disposed within the reaction chamber 1 for supporting a wafer a, a heater 3 disposed below the base 2, a gas inlet 4 disposed at the top of the reaction chamber 1, a multi-layer coaxial nozzle 5 disposed at the gas inlet 4 and facing the wafer a, a recovery device 6, and a control system; the multi-layer coaxial nozzle 5 includes a first gas channel 51 disposed at the center for conveying a metal-organic source, an isolation channel 52 disposed outside the first gas channel 51, and a second gas disposed outside the isolation channel 52 for conveying a hydride source. The second gas channel 53 includes a phase change heat storage layer 54 disposed on the outer layer of the second gas channel 53, and a heating resistance wire 55 wound on the inner wall of the outer layer of the second gas channel 53. TMGa is introduced into the first gas channel 51, and NH3 is introduced into the second gas channel 53. The phase change temperature of the phase change heat storage layer 54 is 550℃-650℃. The recovery device 6 includes an exhaust port 61 disposed at the bottom of the reaction chamber 1, a waste gas pipe 62 connected to the exhaust port 61, a heat exchanger 63 disposed on the waste gas pipe 62, and a hydride source gas pipe 64 connected to the heat exchanger 63 and leading to the gas inlet 4.

[0025] In this invention, unless otherwise specified, all raw materials / components are commercially available products well known to those skilled in the art.

[0026] As attached Figures 1-3 As shown, in an embodiment of the present invention, the reaction chamber 1 is a cylindrical sealed chamber made of stainless steel. The inner wall is polished to reduce gas flow resistance and particle adhesion. Water cooling channels can be provided on the side walls. The gas inlet 4 is located at the top center and has a circular opening for installing multi-layer coaxial nozzles 5. A base 2 is located at the bottom center, and an exhaust port 61 is provided on the lower part of the side wall for discharging waste gas after the reaction. The base 2 is made of high-purity graphite. The upper surface is provided with a groove for placing the wafer. A heater is provided below to heat the base by radiation and convection. A thermocouple (K-type) is also provided to measure the temperature of the base.

[0027] The multi-layer coaxial nozzle 5 is the core component of this invention. It adopts a multi-layer coaxial structure and is cylindrical in shape. From the inside out, it consists of a first gas channel, an isolation channel, a second gas channel, a phase change heat storage layer, and a protective layer, all of which are annular. The upper end of the first gas channel 51 is connected to the metal-organic source supply pipeline, and the lower end leads to the interior of the reaction chamber. TMGa is carried into the first gas channel 51 by the carrier gas (hydrogen). The isolation channel 52 is connected to the nitrogen supply pipeline, and the nitrogen flow rate is precisely controlled by the mass flow controller. It is used to isolate TMGa and NH3 to prevent them from undergoing pre-reaction in the nozzle to generate AlN or GaN particles. The upper end of the second gas channel 53 is connected to the hydride source supply pipeline, and the lower end leads to the interior of the reaction chamber. NH3 is transported through this channel. The phase change heat storage layer 54 is a closed annular space. The heating resistance wire 55 is embedded in the spiral groove processed on the inner wall surface of the outer side of the second gas channel 53 to directly heat the second gas channel 53. A water-cooling jacket is provided on the side wall of the first gas channel 51 to control the temperature of the first gas channel 51 at 50-100℃ to prevent TMGa decomposition. The layers of the multi-layer coaxial nozzle are connected by flanges or welding. The connection is sealed with metal seals or graphite gaskets to ensure airtightness.

[0028] The heat exchanger in the recovery device 6 is a heat pipe heat exchanger, with the evaporation section located in the exhaust gas channel and the condensation section located on the hydride source gas pipe 64.

[0029] The control system includes multiple functional modules. The temperature measurement module includes multiple thermocouples installed on the upper surface of the base 2, the side wall of the reaction chamber 1, the inner wall of multiple channels in the multi-layer coaxial nozzle 5, the gas inlet, and the exhaust port. The gas flow control module includes multiple mass flow controllers that control the flow rates of TMGa carrier gas, NH3, and N2 respectively. The pressure control module includes a pressure sensor inside the reaction chamber. The power control module uses a thyristor power regulator to adjust the power of the heater 3 and the heating resistance wire 55. Pneumatic valves and solenoid valves are installed in multiple gas pipelines and channel openings to control the on / off state and flow direction of the gas. The entire system is automated through a PLC controller.

[0030] This invention utilizes the natural alteration of the thermal radiation path during the wafer's in-situ / removed state. In production mode, when the wafer is placed on the substrate, the substrate is heated to a growth temperature of 1000-1100°C. The wafer absorbs and blocks the upward thermal radiation from the substrate. At this time, the temperature of the multilayer coaxial nozzle and phase change heat storage layer is mainly maintained by electric heating and waste gas heat exchange, keeping the temperature below 550°C, which is below the phase change temperature, and the phase change heat storage material remains solid. In standby mode, the wafer is removed, and the heating power of the substrate 2 is reduced to the heat preservation power, maintaining the substrate temperature at 8°C. Between 00 and 900℃, the upward thermal radiation from the base directly radiates to the multi-layer coaxial nozzle and phase change heat storage layer, causing the temperature to rise rapidly above the phase change temperature. The phase change heat storage material begins to melt, absorbing a large amount of latent heat and automatically storing energy. The standby mode lasts long enough to complete the unloading and loading of the wafer. In the recovery mode, the base heats up again, and the NH3 supply is restored. The phase change heat storage material releases heat, which is carried away by the NH3 gas flow. This not only accelerates the preheating of NH3 but also assists in the heating time of the base and the reaction chamber, shortening the heating time.

[0031] According to some preferred embodiments, the phase change heat storage layer 54 includes an encapsulation shell 541 disposed outside the second gas channel 53, and an Al-Si eutectic alloy and an inert gas disposed inside the encapsulation shell 541.

[0032] In this embodiment, the encapsulation shell 541 is made of stainless steel and uses Al-12.6%Si eutectic alloy as the phase change heat storage material with a phase change temperature of 577°C. The encapsulation shell 541 has a reserved volume expansion space of 8%-15% and is filled with inert gas. The outer layer of the phase change heat storage layer is provided with a protective layer made of boron nitride ceramic, which has the characteristics of high temperature resistance, insulation and good thermal conductivity. It is used to protect the phase change heat storage layer and internal structure, while reducing heat loss. Furthermore, the bottom wall of the encapsulation shell near the nozzle outlet can be set as a corrugated sheet (such as corrugated molybdenum foil). When the phase change material melts and expands in volume, the force required for the material to push the corrugated diaphragm downward is less than the force required to compress the top gas or baffle upward. Therefore, the hydraulic expansion stress is directed to the bottom of the container, forcing the corrugated diaphragm to deform downward. In the recovery mode and production mode, the phase change heat storage material solidifies and releases heat, shrinks in volume, and the deformation disappears. With the change of the equipment operation cycle, the initial deposits (GaN dust) attached to the nozzle edge will be peeled off.

[0033] A set of extremely fine high-temperature alloy microtubes can be embedded inside the packaging shell. The upper end of the microtubes is connected to the isolation channel, and a small portion of N2 gas used for isolation is guided into the microtubes. As the N2 gas flowing through the microtubes undergoes volume thermal expansion, its pressure and flow rate surge instantaneously, forming a hot gas flow that is directly guided to the outlet end of the conical structure, where TMGa and NH3 are pneumatically isolated at the nozzle outlet.

[0034] According to some preferred embodiments, the multi-layer coaxial nozzle 5 further includes a baffle 56 disposed in the second gas channel 53 and extending to the nozzle at its bottom end; the outlet end of the multi-layer coaxial nozzle 5 is tapered and has an extension section 58 at its lower end; the multi-layer coaxial nozzle 5 further includes a distribution cavity 57 disposed at the gas inlet 4 and connected to the first gas channel 51, the isolation channel 52 and the second gas channel 53.

[0035] In this embodiment, the partition 56 has multiple vent holes, which allow gas to flow between the two sub-channels, making the gas flow more uniform and allowing for more thorough preheating. When the nozzle is closed, the end of the partition 56 abuts against the nozzle port stop, forming a circulation channel in the second gas channel for cleaning during equipment maintenance. The nozzle outlet end is set with a conical structure, and the cone angle can be designed to be 20° to control the airflow speed, achieve laminar flow, and optimize the mixing of TMGa and NH3. Furthermore, the length endpoints of each layer of channels inside the nozzle are set at different heights, that is, the outlets of the first gas channel for conveying TMGa and the isolation channel for conveying the N2 isolation curtain extend downward by 2-5 mm, making them slightly protrude from the outlet of the second gas channel for conveying NH3. This ensures that after the high-temperature NH3 leaves the nozzle, TMGa is still tightly wrapped by the physical tube wall and the N2 curtain, forcibly pushing the physical mixing point of TMGa and NH3 away from the nozzle end face and suspending it in the free space of the reaction chamber, avoiding severe pre-reaction at the outlet end of the conical structure, generating dust particles and clogging the nozzle.

[0036] This invention also provides an energy-saving method for the above-described standby energy-saving structure system, comprising the following steps: a power-on preheating step: loading the wafer onto the substrate, turning on the heater to heat the substrate, and turning on the heating resistance wire to preheat the second gas channel; an epitaxial growth step: after the substrate reaches the growth temperature, supplying TMGa to the first gas channel, supplying NH3 to the second gas channel, and supplying N2 to the isolation channel, so that NH3 is preheated in the nozzle and mixed with TMGa to perform GaN thin film epitaxial growth; a standby energy-saving step: after the wafer is removed from the substrate, stopping... The gas supply is provided to the first gas channel and the second gas channel, while the isolation channel retains a trace amount of N2 supply. The heating power of the heater is reduced from the growth power to the heat preservation power. The thermal radiation from the substrate is radiated to the phase change heat storage layer. The phase change heat storage material in the phase change heat storage layer melts, absorbs heat, and stores thermal energy. Rapid recovery step: When the wafer is newly loaded onto the substrate, the heating power of the heater is restored to the growth power, and the supply to the first gas channel and the second gas channel is restored. The phase change heat storage layer solidifies, releases heat, and preheats the second gas channel. In the epitaxial growth step, NH3 is preheated to 550℃-650℃ in the nozzle before being ejected.

[0037] In this embodiment, the specific operation of power-on preheating is as follows: The operator loads the wafer onto the base 2, closes the top cover of the reaction chamber, tightens the bolts, starts the vacuum system, and starts the heating program. In the first stage, the heater raises the base temperature from room temperature to 800 degrees Celsius. In the second stage, the base temperature is raised to 1000 degrees Celsius. In the third stage, the temperature is stabilized at 1050 degrees Celsius. At the same time, the heating resistance wire is also activated to preheat the second gas channel. When the wall temperature of the second gas channel reaches above 300 degrees Celsius, the preheating is considered complete.

[0038] The specific operation of epitaxial growth is as follows: First, the N2 supply to the isolation channel is turned on, forming an effective isolation gas curtain between the metal-organic source and the hydride source, but without excessively diluting the reaction gas. N2 is ejected from the isolation channel, forming a downward airflow in the reaction chamber. Then, the NH3 supply to the second gas channel is turned on. After entering the second gas channel 53, the NH3 comes into contact with the channel wall during the flow and is preheated by the heating resistance wire 55. Next, the TMGa supply to the first gas channel 51 is turned on. The TMGa gas is ejected from the first gas channel and mixes with NH3 at the nozzle. The mixed gas undergoes a chemical reaction on the surface of wafer a. The reaction byproduct CH4 and excess H2, N2, and NH3 flow downward together and are discharged from the exhaust port. During the continuous growth process, the temperature, pressure, and flow rate are controlled by the control system.

[0039] The specific operation for standby energy saving is as follows: The operator first gradually reduces the power of the heater, and at the same time, stops supplying TMGa to the first gas channel, stops supplying NH3 to the second gas channel, maintains the N2 supply to the isolation channel, maintains the positive pressure in the reaction chamber, and prevents external air from entering. At this time, the heat flow from the base directly radiates upwards to the nozzle and is absorbed by the phase change heat storage layer. The Al-Si eutectic alloy begins to absorb heat and the temperature rises. When the temperature reaches the melting point, the alloy begins to melt. The melting process continues, and the alloy gradually changes from a solid state to a liquid state.

[0040] The rapid recovery operation is as follows: The operator loads the new wafer onto the substrate, increases the heater power, and resumes the supply of raw material gas to the first and second gas channels. As the substrate temperature rises, thermal radiation increases, but at this time, the Al-Si eutectic alloy in the phase change heat storage layer is still in a liquid state. Due to the obstruction of the wafer, the heat absorbed by the Al-Si eutectic alloy begins to decrease, and the alloy temperature begins to drop. When the temperature drops below 577 degrees Celsius, the alloy begins to solidify. The solidification process releases latent heat, which is transferred to the NH3 in the channels through the outer wall of the encapsulation shell and the second gas channel, so that the NH3 is fully preheated. Therefore, when the substrate temperature recovers to the growth temperature, the NH3 has also been preheated, and the system can immediately start epitaxial growth.

[0041] Preferably, the process further includes the following steps: waste heat recovery step: the waste gas in the reaction chamber enters the waste gas pipeline through the exhaust port, and exchanges heat with the NH3 to be supplied when it flows through the heat exchanger. The waste heat of the waste gas is used to preheat the NH3 to be supplied. The preheated NH3 is then introduced to the gas inlet through the hydride source gas pipeline.

[0042] In this embodiment, the recovery device operates continuously throughout the entire operation. The waste gas enters the waste gas pipeline, flows through the heat exchanger, and the high-temperature waste gas transfers heat to the heat exchanger tube wall, which in turn transfers it to the NH3 inside. The NH3 to be supplied comes out of the cylinder, first passes through the pressure reducing valve, and then enters the heat exchanger. In the heat exchanger, it absorbs the heat from the waste gas and undergoes preliminary preheating before being transported to the gas inlet through the hydride source gas pipeline. It then enters the second gas channel of the multi-layer coaxial nozzle. After heat exchange, the temperature of the waste gas decreases and it continues to be discharged to subsequent treatment equipment (such as the tail gas treatment tower).

[0043] The structural system of this invention can be adapted to different MOCVD application scenarios. This embodiment is applicable to GaN-based LED production. By adjusting the number of nozzle layers and the composition of the phase change heat storage layer, it can be applied to AlGaN-based deep ultraviolet LED production and InGaN-based blue-green LED production.

[0044] The aforementioned heat exchanger, distribution chamber, electrical components in the control system, heater, base, etc., are all well known to those skilled in the art, and will not be described in detail here.

[0045] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. A standby energy-saving structural system, characterized in that, The system includes a reaction chamber (1), a base (2) disposed in the reaction chamber (1) for supporting a wafer (a), a heater (3) disposed below the base (2), a gas inlet (4) disposed at the top of the reaction chamber (1), a multi-layer coaxial nozzle (5) disposed at the gas inlet (4) and facing the wafer (a), and a control system; the multi-layer coaxial nozzle (5) includes a first gas channel (51) disposed at the center for conveying a metal-organic source, an isolation channel (52) disposed on the outer layer of the first gas channel (51), a second gas channel (53) disposed on the outer layer of the isolation channel (52) for conveying a hydride source, a phase change heat storage layer (54) disposed on the outer layer of the second gas channel (53), and a heating resistance wire (55) wound on the inner wall of the outer layer of the second gas channel (53).

2. The standby energy-saving structure system according to claim 1, characterized in that, The first gas channel (51) is conditioned on TMGa, the second gas channel (53) is conditioned on NH3, and the phase change temperature of the phase change heat storage layer (54) is 550℃-650℃.

3. The standby energy-saving structure system according to claim 2, characterized in that, It also includes a recovery device (6); the recovery device (6) includes an exhaust port (61) located at the bottom of the reaction chamber (1), a waste gas pipe (62) connected to the exhaust port (61), a heat exchanger (63) located on the waste gas pipe (62), and a hydride source gas pipe (64) connected to the heat exchanger (63) and leading to the gas inlet (4).

4. The standby energy-saving structure system according to claim 3, characterized in that, The multi-layer coaxial nozzle (5) also includes a baffle (56) disposed in the second gas channel (53) and extending to the nozzle at its bottom end.

5. The standby energy-saving structure system according to claim 3, characterized in that, The phase change heat storage layer (54) includes an encapsulation shell (541) disposed outside the second gas channel (53), and an Al-Si eutectic alloy and an inert gas disposed inside the encapsulation shell (541).

6. The standby energy-saving structure system according to claim 3, characterized in that, The multi-layer coaxial nozzle (5) also includes a distribution chamber (57) disposed at the gas inlet (4) and connected to the first gas channel (51), the isolation channel (52), and the second gas channel (53).

7. The standby energy-saving structure system according to claim 3, characterized in that, The outlet end of the multi-layer coaxial nozzle (5) is set in a conical shape, and the lower end is provided with an extension section (58).

8. An energy-saving method for the standby energy-saving structure system according to any one of claims 3 to 7, Its features are, Includes the following steps: Power-on preheating steps: Load the wafer onto the substrate, turn on the heater to heat the substrate, and turn on the heating resistance wire to preheat the second gas channel; Epitaxial growth step: When the substrate reaches the growth temperature, TMGa is supplied to the first gas channel, NH3 is supplied to the second gas channel, and N2 is supplied to the isolation channel. After the NH3 is preheated in the nozzle, it is mixed and reacted with TMGa to carry out epitaxial growth of GaN thin film. Standby power saving steps: After the wafer is removed from the substrate, the supply to the first gas channel and the second gas channel is stopped, the isolation channel retains a small amount of N2 supply, the heating power of the heater is reduced from the growth power to the heat preservation power, the heat radiation of the substrate is radiated to the phase change heat storage layer, and the phase change heat storage material in the phase change heat storage layer melts, absorbs heat and stores thermal energy. Rapid recovery step: When the wafer is newly loaded onto the substrate, the heating power of the heater is restored to the growth power, and the supply to the first gas channel and the second gas channel is restored. The phase change heat storage layer solidifies and releases heat energy to preheat the second gas channel.

9. The energy-saving method according to claim 8, characterized in that, It also includes the following steps: Waste heat recovery step: The waste gas in the reaction chamber enters the waste gas pipeline through the exhaust port, and exchanges heat with the NH3 to be supplied when it flows through the heat exchanger. The waste heat of the waste gas is used to preheat the NH3 to be supplied. The preheated NH3 is then introduced to the gas inlet through the hydride source gas pipe.

10. The energy-saving method according to claim 8, characterized in that, In the epitaxial growth step, NH3 is preheated to 550℃-650℃ inside the nozzle before being sprayed out.

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