A reaction chamber for observing a flow field, a method of observing a flow field

Abstract

The application provides a reaction cavity for observing a flow field and a method for observing a flow field. The reaction cavity for observing a flow field comprises a shower head extension rod, a gas guide pipe and a flow field observation assembly. The first inert gas is introduced into the reaction cavity by the shower head, and the second inert gas is introduced into the reaction cavity by the gas guide pipe. Since the refractive indexes of the first inert gas and the second inert gas are different, when parallel light passes through the first air hole, the original light path is deflected, the light cannot be converged at the focal point after being reflected by the concave mirror, and the light is blocked by the baffle to form a schlieren image at the optical receiving element. The flow field distribution of the gas flow sprayed by the first air hole can be observed by using the schlieren image. The reaction cavity can directly observe, simulate and control the gas flow distribution of the semiconductor material epitaxial growth cavity by using the principle that the light path is deflected due to the difference in the refractive indexes of different gases, and is beneficial to the uniformity control of the semiconductor material epitaxial growth.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a reaction chamber for observing flow fields and a method for observing flow fields. Background Technology

[0002] The uniformity of the flow field in the epitaxial growth chamber of semiconductor materials is a crucial factor determining the uniformity of the thickness, composition, and material quality of the epitaxial layer. During epitaxial growth, the semiconductor material growth source is colorless, and the growth chamber requires extremely high cleanliness to prevent the introduction of impurities such as colorants. This makes it difficult to visually observe the flow field within the epitaxial growth chamber. Furthermore, simulation software for flow field analysis struggles to fully incorporate the complexities of the actual environment into the simulation system, making it difficult to accurately reflect the internal flow field distribution within the epitaxial growth chamber.

[0003] To address the current issues of the difficulty in visually observing the field and the inability of simulation software to accurately reflect the flow field distribution inside the epitaxial growth chamber, it is necessary to make improvements. Summary of the Invention

[0004] In view of this, the present invention proposes a reaction chamber for observing flow fields and a method for observing flow fields, so as to solve the technical problems existing in the prior art.

[0005] In a first aspect, the present invention provides a reaction cavity for observing a flow field, comprising:

[0006] The reaction chamber has observation windows on its side walls;

[0007] A spray head is located inside the reaction chamber. The upper end of the spray head extends out of the reaction chamber, and the lower end of the spray head is provided with multiple spray holes. The spray head is used to introduce a first inert gas into the reaction chamber.

[0008] A spray head extension rod is connected to the lower end of the spray head. A first vent hole is provided on the spray head extension rod corresponding to the spray hole. A second vent hole is provided inside the spray head extension rod between any two adjacent first vent holes. The second vent hole connects to two adjacent first vent holes.

[0009] The spray head extension rod is provided with a second valve at the junction of the first vent and the second vent, and a first valve is provided above the second valve in the first vent.

[0010] A gas guide tube is located outside the reaction chamber. One end of the gas guide tube extends into the reaction chamber and communicates with a second vent near the inner wall of the reaction chamber. The gas guide tube is used to introduce a second inert gas into the reaction chamber.

[0011] The flow field observation component includes:

[0012] A parallel light generating element is located on one side of the outside of the reaction chamber. The parallel light generating element is used to emit parallel light and pass through the observation window. The parallel light covers part or all of the first vent.

[0013] A concave mirror, located on the other side of the reaction chamber, is used to receive and reflect parallel light;

[0014] The baffle is located at the focal point of the parallel light rays reflected by the concave mirror.

[0015] An optical receiving element is located on one side of the baffle, and the optical receiving element receives light after passing through the baffle and forms an image;

[0016] The parallel light emitted by the parallel light generating element is deflected after passing through the first vent hole, reflected by the concave mirror, blocked by the baffle, and forms a schlieren image at the optical receiving element.

[0017] Preferably, in the reaction chamber for observing the flow field, the side wall of the reaction chamber is provided with a vent hole corresponding to the second vent hole near the inner wall of the reaction chamber. One end of the vent pipe passes through the vent hole and communicates with the second vent hole. A sealing ring is provided at the connection between the vent pipe and the second vent hole.

[0018] Preferably, the reaction chamber for observing the flow field further includes:

[0019] A tray, located within the reaction chamber and below the spray head extension rod;

[0020] A drive mechanism that connects to the tray and drives the tray to rotate about its central axis.

[0021] Preferably, the reaction chamber for observing the flow field further includes a heating element located on the tray for heating the tray.

[0022] Preferably, the reaction chamber for observing the flow field further includes a vacuum system located outside the reaction chamber, which is used to evacuate the reaction chamber.

[0023] Preferably, the reaction chamber for observing the flow field includes any one of a metal-organic chemical vapor deposition chamber, a magnetron sputtering chamber, and a molecular beam epitaxy chamber.

[0024] Preferably, the gas guide pipe of the reaction chamber used for observing the flow field is equipped with a valve.

[0025] Preferably, in the reaction chamber for observing the flow field, each of the first valves independently controls the opening or closing of the multiple first vent holes, and each of the second valves independently controls the opening or closing of the multiple first vent holes and the multiple second vent holes.

[0026] Secondly, the present invention also provides a method for observing a flow field using the aforementioned reaction cavity for observing the flow field, comprising the following steps:

[0027] Selectively open the first valve inside the first vent hole, and use the spray head to introduce the first inert gas into the reaction chamber, so that the first vent hole is filled with the first inert gas.

[0028] A second inert gas is introduced into the reaction chamber through a gas delivery tube. The second valve is selectively opened and the first valve is closed, so that the second inert gas flows into the first vent through the second vent.

[0029] Parallel light emitted by the parallel light generating element passes through the first vent. The different refractive indices of the first and second inert gases cause the parallel light to be deflected. The deflected light path is blocked by a baffle after passing through the concave mirror, and a schlieren is formed at the optical receiving element. The gas flow field distribution is obtained by calculation using the schlieren.

[0030] Preferably, the method for observing the flow field further includes, before introducing the second inert gas into the reaction chamber:

[0031] Heat the tray to the set temperature;

[0032] Drive the tray to rotate at a set speed;

[0033] The reaction chamber is evacuated to the set vacuum level.

[0034] The reaction chamber and method for observing flow fields of the present invention have the following advantages over the prior art:

[0035] 1. The reaction chamber for observing the flow field of the present invention includes a spray head extension rod, a duct, and a flow field observation component. The spray head extension rod is provided with a first vent and a second vent, and the first vent is provided with a first valve and a second valve. A first inert gas is introduced into the reaction chamber through the spray head, and a second inert gas is introduced into the reaction chamber through the duct. Due to the different refractive indices of the first and second inert gases, when parallel light passes through the first vent, the original light path is deflected due to the difference in refractive indices of the first and second inert gases. After being reflected by the concave mirror, the light cannot converge to the focal point and is blocked by the baffle, forming a schlieren image at the optical receiving element. The flow field distribution of the airflow sprayed through the first vent can be observed using this schlieren image. The reaction chamber of the present invention utilizes the principle of light path deflection caused by the difference in refractive indices of different gases to directly observe, simulate, and control the airflow distribution in the epitaxial growth chamber of semiconductor materials, which is beneficial to the uniformity control of the epitaxial growth of semiconductor materials.

[0036] 2. The method for observing the flow field of the present invention can completely replicate the reaction chamber parameters and epitaxial growth environment within the reaction cavity. By utilizing the difference in refractive index of different inert gases to deflect incident parallel light rays, and by selecting the light rays at the focal point using a light baffle, schlieren with different contrasts can be formed at the imaging end, allowing observation of the evolution of the airflow field at a specific vent. Furthermore, based on the airflow field distribution results, the airflow parameters can be further adjusted to achieve specific smoothness requirements, which is beneficial for efficiently improving the uniformity of epitaxial growth of nitride semiconductor materials. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. 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.

[0038] Figure 1 This is a schematic cross-sectional view of the reaction chamber used for observing the flow field in one embodiment of the present invention;

[0039] Figure 2 This is a side view of the spray head extension rod in one embodiment of the present invention;

[0040] Figure 3 This is a side cross-sectional view of the spray head extension rod in one embodiment of the present invention;

[0041] Figure 4 This is a front view of the spray head extension rod in one embodiment of the present invention;

[0042] Figure 5This is a top view of the spray head extension rod in one embodiment of the present invention;

[0043] Figure 6 This is a schematic diagram of the optical path of the reaction cavity for observing the flow field in a non-operating state in one embodiment of the present invention;

[0044] Figure 7 This is a schematic diagram of the optical path for observing the working state of the reaction cavity in one embodiment of the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0047] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0048] In the description of this invention, it should be understood that the orientation or positional relationship indicated by terms such as "above" is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use, or the orientation or positional relationship in which those skilled in the art are usually understood. It is only for the convenience of describing this invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0049] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0051] This invention provides a reaction cavity for observing flow fields, such as Figures 1-6 As shown, it includes:

[0052] The reaction chamber 1 has an observation window 11 on its side wall;

[0053] Spray head 2 is located inside reaction chamber 1. The upper end of spray head 2 extends outside reaction chamber 1, and the lower end of spray head 2 is provided with multiple spray holes 21. Spray head 2 is used to introduce a first inert gas into reaction chamber 1.

[0054] The spray head extension rod 3 is connected to the lower end of the spray head 21. A first vent 31 is provided on the spray head extension rod 3 at the spray hole 21. A second vent 32 is provided inside the spray head extension rod 31 between any two adjacent first vent holes 31. The second vent 32 connects the two adjacent first vent holes 31.

[0055] Among them, a second valve 4 is provided inside the spray head extension rod 3 at the connection between the first vent 31 and the second vent 32, and a first valve 5 is provided inside the first vent 31 above the second valve 4.

[0056] The gas guide tube 6 is located outside the reaction chamber 1. One end of the gas guide tube 6 extends into the reaction chamber 1 and is connected to the second vent 32 near the inner wall of the reaction chamber 1. The gas guide tube 6 is used to introduce a second inert gas into the reaction chamber 1.

[0057] Flow field observation component 7 includes:

[0058] Parallel light generating element 71 is located on one side outside the reaction chamber 1. The parallel light generating element is used to emit parallel light and pass through the observation window. The parallel light covers part or all of the first vent hole.

[0059] A concave mirror 72 is located on the other side outside the reaction chamber 1. The concave mirror 72 is used to receive and reflect parallel light.

[0060] Baffle 73 is located at the focal point of the parallel light rays reflected by the concave mirror;

[0061] An optical receiving element 74 is located on one side of the baffle 73. The optical receiving element 74 receives the light after passing through the baffle and forms an image.

[0062] Parallel light emitted by the parallel light generating element 71 is deflected after passing through the first vent 31, reflected by the concave mirror 72, and then blocked by the baffle 73, forming a schlieren image at the optical receiving element 74.

[0063] It should be noted that the reaction chamber for observing the flow field of the present invention includes a reaction chamber 1, a spray head 2, a spray head extension rod 3, a vent pipe 6, and a flow field observation component 7; wherein, the reaction chamber 1 is hollow inside, and the interior of the reaction chamber 1 is a chamber for epitaxial growth of semiconductor material; the spray head 2 is located in the reaction chamber 1, with its upper end extending out of the reaction chamber 1 and its lower end located inside the reaction chamber 1, and a plurality of spray holes 21 are provided at intervals at the lower end of the spray head 2; the spray head extension rod 3 is located at the lower end of the spray head 2, and a plurality of first vent holes 31 are provided on the spray head extension rod 3, and the plurality of first vent holes 31 are provided on the spray head extension rod 3. A vent 31 corresponds one-to-one with multiple spray holes 21, and the first vent 31 and the spray holes 21 are interconnected. The first vent 31 penetrates the upper and lower end faces of the spray head extension rod 3. A second vent 32 is provided inside the spray head extension rod 31 between any two adjacent first vent holes 31, and the second vent 32 connects the two adjacent first vent holes 31. A first valve 5 is provided inside each first vent hole 31 and above the second vent hole 32. The first valve 5 is used to control the opening or closing of the first vent hole 31. A second valve 4 is provided at the connection between the vent 31 and the second vent 32. The second valve 4 is located below the first valve and is used to control the opening or closing of the connection between the first vent 31 and the second vent 32. A vent pipe 6 is located outside the reaction chamber 1. One end of the vent pipe 6 extends into the reaction chamber 1 and connects with the second vent 32 near the inner wall of the reaction chamber 1. That is, the vent pipe 6 connects with the second vent 32 on the outermost side of the spray head extension rod 3. The flow field observation assembly 7 includes: a parallel light generating element 71, a concave mirror 72, a baffle 73, and an optical receiving element. 74; wherein, the parallel light generating element 71 is located in the observation window, and after the parallel light generating element 71 emits parallel light, it passes through the observation window. The coverage area of ​​the parallel light covers at least part or all of the first vent 31 on the spray head extension rod 3. After the parallel light passes through the first vent 31, it is incident on the concave mirror 72. When the parallel light is incident on the concave mirror 72, it is reflected by the concave mirror 72 and focused at the focal point of the concave mirror 72. The baffle 73 is set at the focal point of the concave mirror 72. The optical receiving element 74 is used to receive the light after it has passed through the baffle 73 and form an image.

[0064] Specifically, the working principle of the reaction chamber used for observing the flow field is as follows: First, a first inert gas is introduced into the reaction chamber through the spray head 2. The first inert gas enters the spray hole 21, and at the same time, the first valve 5 is opened (at this time, the second valve 4 is closed), so that the first inert gas fills the first vent hole 31. Then, the first valve 5 in the first vent hole 31 where the flow field needs to be observed is closed to prevent the first inert gas from continuing to enter the first vent hole 31. At the same time, the second valve 4 is opened, and the second inert gas is introduced into the reaction chamber through the air guide pipe 6. Due to the opening of the second valve 4, the second vent hole 32 and the second inert gas are introduced into the reaction chamber. When the first vent 31 is open, the second inert gas enters the first vent 31 along the second vent 32. Since the first and second inert gases have different refractive indices, when parallel light passes through the second valve 4 in the first vent 31, the original light path will be deflected due to the difference in refractive indices. After being reflected by the concave mirror 72, the light cannot converge to the focal point and is blocked by the baffle 73. A schlieren image is formed at the optical receiving element 74. The flow field distribution of the sprayed airflow in the first vent 31 can be observed using this schlieren image.

[0065] Specifically, the principle of forming a schlieren image at the optical receiving element 74 as described in this invention is based on the fact that the refractive index of light in the measured medium is proportional to the airflow density of the flow field. Therefore, the numerical schlieren is a density gradient cloud map. By filtering out the light that changes through the refractive index through the filter aperture, the change of refractive index in the perturbation area can be visualized on the imaging surface.

[0066] Specifically, the inert gases mentioned in this invention include gases such as helium (He), neon (Ne), argon (Ar), krypton (Kr), and xenon (Xe). The first and second inert gases are different inert gases with different refractive indices. The difference in refractive index of the different inert gases is used to deflect the incident parallel light rays. By selecting the light rays at the focal point through a light baffle, schlieren images with different contrasts are formed at the imaging end, and the evolution of the airflow field at a specific vent can be observed.

[0067] In some embodiments, the optical receiving element 74 may be an optical receiving element such as a CCD. The optical receiving element 74 receives the light after it passes through the baffle, forms an image, and transmits it to the computer system for display and storage.

[0068] In some embodiments, the viewing window can transmit parallel light, and the specific viewing window can be made of transparent glass material.

[0069] In some embodiments, a vent hole is provided on the side wall of the reaction chamber 1 at the second vent hole 32 near the inner wall of the reaction chamber 1. One end of the vent pipe 6 passes through the vent hole and communicates with the second vent hole 32. A sealing ring 33 is provided at the connection between the vent pipe 6 and the second vent hole 32.

[0070] In the above embodiment, a sealing ring 33 is provided at the connection between the air guide pipe 6 and the second vent 32 to prevent the leakage of the second inert gas from disturbing the flow field.

[0071] In some embodiments, it also includes:

[0072] Tray 8 is located inside reaction chamber 1 and below spray head extension rod 3;

[0073] The drive mechanism 81 connects to the tray and drives the tray 8 to rotate around its central axis.

[0074] In the above embodiments, the drive mechanism includes, but is not limited to, an adjustable speed motor including a servo motor, a stepper motor or a frequency converter motor, etc. The drive mechanism 81 is connected to the central axis of the tray 8, and the drive mechanism 81 drives the tray to rotate around its central axis.

[0075] In some embodiments, a heating element 82 is also included, which is located on the tray 8 for heating the tray 8.

[0076] In the above embodiment, the heating element 82 is an electric heating element. The heating element 82 is set at the lower end of the tray and heats the tray 8. Specifically, in practice, a rotating shaft 83 is provided at the lower end of the tray 8 and at its central axis. The rotating shaft 83 is connected to the driving mechanism 81. The driving mechanism 81 drives the rotating shaft 83 to rotate, thereby realizing the rotation of the tray 8. The heating element 82 is sleeved on the outer periphery of the rotating shaft 83, and the heating element 82 can rotate relative to the rotating shaft 83.

[0077] In some embodiments, a vacuum system 9 is also included, which is located outside the reaction chamber 1, and the vacuum system 9 is used to evacuate the reaction chamber 1.

[0078] In some embodiments, the reaction chamber 1 includes, but is not limited to, semiconductor thin film epitaxial growth deposition chambers such as metal-organic chemical vapor deposition chambers, magnetron sputtering chambers, and molecular beam epitaxy chambers.

[0079] In some embodiments, the air duct 6 is provided with a valve.

[0080] In some embodiments, the plurality of first valves 5 independently control the opening or closing of the plurality of first vent holes 31, and the plurality of second valves 4 independently control the opening or closing of the plurality of first vent holes 31 and second vent holes 32.

[0081] In the above embodiment, since the multiple first valves 5 and multiple second valves 4 are each controlled independently, the gas flow field inside one or more first vent holes 31 can be observed at different positions as needed. Specifically, in practice, the gas flow field inside the first vent hole 31 at different angles can also be obtained by changing the angle of the flow field observation component, the incident angle of parallel light, etc.

[0082] For further details, please refer to the following: Figure 6 As shown, it shows the state when the reaction chamber is not working. Since the first inert gas and the second inert gas are not introduced at this time, the parallel light emitted by the parallel light generating element 71 will not be deflected when it passes through the first vent. After the parallel light is incident on the concave mirror 72, it is reflected by the concave mirror 72 and focused on the focal point of the concave mirror 72. The baffle 73 is located at the focal point of the concave mirror 72.

[0083] Based on the same inventive concept, the present invention also provides a method for observing a flow field using the above-mentioned reaction cavity for observing a flow field, comprising the following steps:

[0084] S1. Selectively open the first valve in the first vent hole and use the spray head to introduce the first inert gas into the reaction chamber, so that the first vent hole is filled with the first inert gas.

[0085] S2. Use the gas guide tube to introduce the second inert gas into the reaction chamber, selectively open the second valve and close the first valve, so that the second inert gas flows into the first vent through the second vent.

[0086] S3. Parallel light emitted by the parallel light generating element passes through the first vent. The refractive indices of the first and second inert gases are different, causing the parallel light to be deflected. The deflected light path is blocked by a baffle after passing through the concave mirror, and a schlieren image is formed at the optical receiving element. The gas flow field distribution is obtained by calculation using the schlieren image.

[0087] In the above embodiments, since the reaction chamber of the present invention includes multiple first vent holes, the gas flow field distribution within one or more of the first vent holes can be observed in practice. The specific gas flow field distribution within the first vent hole to be observed is determined according to need. The specific observation method includes: S1. First, determining the gas flow field distribution within the first vent hole to be observed as needed, and accordingly opening the first valve within the first vent hole to be observed, and using a spray head to introduce a first inert gas into the reaction chamber, filling the first vent hole with the first inert gas. It can be understood that at this time, the reaction chamber is also filled with the first inert gas, completing the atmosphere adjustment within the reaction chamber; S2. Second, using a gas guide pipe to introduce a first... Two inert gases are introduced. Simultaneously, the first valve in the first vent hole to be observed is closed to prevent the first inert gas from continuing to flow into the first vent hole. At the same time, the second valve is opened, allowing the second inert gas to flow into the first vent hole through the second vent hole. S3, after the parallel light emitted by the parallel light generating element passes through the first vent hole, the parallel light is deflected due to the difference in refractive index between the first and second inert gases. The deflected light path is blocked by a baffle after passing through the concave mirror, and a schlieren image is formed at the optical receiving element. The gas flow field distribution is obtained by calculation using the schlieren image. This invention observes the airflow distribution and evolution law of different growth source input sites through optical methods, and deduces the overall airflow field distribution during epitaxial growth.

[0088] In some embodiments, before introducing the second inert gas into the reaction chamber, the process further includes: heating the tray to a set temperature; driving the tray to rotate at a set speed; and evacuating the reaction chamber to a set vacuum level.

[0089] In the above embodiments, in order to improve the accuracy of the flow field observation results, before introducing the second inert gas, the tray is heated to a set temperature, driven to rotate at a set speed, and the reaction chamber is evacuated to a set vacuum level. The specific heating temperature, tray rotation speed, and vacuum level are the same as those during the actual epitaxial growth of semiconductor materials. This ensures that the reaction chamber parameters and epitaxial growth environment within the reaction chamber are completely replicated when observing the flow field, thereby improving the accuracy of the observation results. Specifically, the airflow parameters can be further adjusted based on the airflow field distribution results to achieve specific smoothness requirements, which is beneficial for efficiently improving the uniformity of epitaxial growth of nitride semiconductor materials.

[0090] For further details, please refer to... Figure 7 As shown, it illustrates that after parallel light passes through the first vent, the light is deflected due to the difference in refractive indices between the first and second inert gases. Figure 7 In diagram a, the light path of the parallel light before deflection (i.e., the light path shown by the dashed line in the figure) is shown, and in diagram b, the light path after deflection. Figure 7It can be clearly seen that parallel light is deflected, and the deflected light path is blocked by a baffle after passing through a concave mirror, thus forming a schlieren image at the optical receiving element.

[0091] The following further illustrates the method for observing flow fields according to the present invention with specific embodiments. This section further describes the content of the present invention in conjunction with specific embodiments, but it should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the methods and equipment used in the present invention are conventional methods and equipment in the art.

[0092] Example 1

[0093] This application provides a method for observing a flow field, including the following steps:

[0094] S1. Open the first valve in the first vent hole and use the spray head to introduce helium into the reaction chamber, so that the first vent hole is filled with helium. This step completes the adjustment of the atmosphere in the reaction chamber.

[0095] S2. Heat the tray to the set temperature, drive the tray to rotate at the set speed, and evacuate the reaction chamber to the set vacuum level; wherein, the heating temperature, tray speed, and vacuum level are the same as those during the actual epitaxial growth of semiconductor materials; through this step, the working conditions in the reaction chamber are adjusted to be the same as the environment during the actual epitaxial growth of semiconductor materials.

[0096] S3. Xenon gas is introduced into the reaction chamber through the gas guide tube. The second valve is selectively opened and the first valve is closed, so that the xenon gas flows into the first vent through the second vent. This step prevents helium gas from entering the first vent. At the same time, by selectively opening the second valve and closing the first valve, the flow field distribution of the airflow in the first vent at different positions can be observed. The angle of the flow field observation component can also be adjusted to observe the gas flow field distribution in the first vent at different angles.

[0097] S4. By utilizing the different refractive indices of helium and xenon, parallel light is deflected, thereby forming a schlieren image at the optical receiving element. The gas flow field distribution in a certain first vent at a certain angle or position is obtained by calculation using the schlieren image. The overall gas flow field result of the reaction chamber is obtained by computer software simulation and calculation.

[0098] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A reaction chamber for observing a flow field, characterized in that, include: The reaction chamber has observation windows on its side walls; A spray head is located inside the reaction chamber. The upper end of the spray head extends out of the reaction chamber, and the lower end of the spray head is provided with multiple spray holes. The spray head is used to introduce a first inert gas into the reaction chamber. A spray head extension rod is connected to the lower end of the spray head. A first vent hole is provided on the spray head extension rod corresponding to the spray hole. A second vent hole is provided inside the spray head extension rod between any two adjacent first vent holes. The second vent hole connects to two adjacent first vent holes. The spray head extension rod is provided with a second valve at the junction of the first vent and the second vent, and a first valve is provided above the second valve in the first vent. A gas guide tube is located outside the reaction chamber. One end of the gas guide tube extends into the reaction chamber and communicates with a second vent near the inner wall of the reaction chamber. The gas guide tube is used to introduce a second inert gas into the reaction chamber. The flow field observation component includes: A parallel light generating element is located on one side of the outside of the reaction chamber. The parallel light generating element is used to emit parallel light and pass through the observation window. The parallel light covers part or all of the first vent. A concave mirror, located on the other side of the reaction chamber, is used to receive and reflect parallel light; The baffle is located at the focal point of the parallel light rays reflected by the concave mirror. An optical receiving element is located on one side of the baffle, and the optical receiving element receives light after passing through the baffle and forms an image; The parallel light emitted by the parallel light generating element is deflected after passing through the first vent hole, reflected by the concave mirror, blocked by the baffle, and forms a schlieren image at the optical receiving element.

2. The reaction chamber for observing the flow field as described in claim 1, characterized in that, A vent hole is provided on the side wall of the reaction chamber, corresponding to the second vent hole near the inner wall of the reaction chamber. One end of the vent pipe passes through the vent hole and communicates with the second vent hole. A sealing ring is provided at the connection between the vent pipe and the second vent hole.

3. The reaction chamber for observing the flow field as described in claim 1, characterized in that, Also includes: A tray, located within the reaction chamber and below the spray head extension rod; A drive mechanism that connects to the tray and drives the tray to rotate about its central axis.

4. The reaction chamber for observing the flow field as described in claim 3, characterized in that, It also includes a heating element located on the tray for heating the tray.

5. The reaction chamber for observing the flow field as described in claim 1, characterized in that, It also includes a vacuum system located outside the reaction chamber, which is used to evacuate the reaction chamber.

6. The reaction chamber for observing the flow field as described in claim 1, characterized in that, The reaction chamber includes any one of the following: a metal-organic chemical vapor deposition chamber, a magnetron sputtering chamber, and a molecular beam epitaxy chamber.

7. The reaction chamber for observing the flow field as described in claim 1, characterized in that, The air duct is equipped with a valve.

8. The reaction chamber for observing the flow field as described in any one of claims 1 to 7, characterized in that, Each of the first valves independently controls the opening or closing of the multiple first vent holes, and each of the second valves independently controls the opening or closing between the multiple first vent holes and the multiple second vent holes.

9. A method for observing a flow field using a reaction chamber for observing a flow field as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Selectively open the first valve inside the first vent hole, and use the spray head to introduce the first inert gas into the reaction chamber, so that the first vent hole is filled with the first inert gas. A second inert gas is introduced into the reaction chamber through a gas delivery tube. The second valve is selectively opened and the first valve is closed, so that the second inert gas flows into the first vent through the second vent. Parallel light emitted by the parallel light generating element passes through the first vent. The different refractive indices of the first and second inert gases cause the parallel light to be deflected. The deflected light path is blocked by a baffle after passing through the concave mirror, and a schlieren image is formed at the optical receiving element. The gas flow field distribution is obtained by calculation using the schlieren image.

10. The method for observing a flow field as described in claim 9, characterized in that, Before introducing the second inert gas into the reaction chamber, the following steps are also included: Heat the tray to the set temperature; Drive the tray to rotate at a set speed; The reaction chamber was evacuated to the set vacuum level; Connect the tray and drive the tray to rotate about its central axis.

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