Gas intake system, semiconductor process equipment and semiconductor doping method

Abstract

An intake system, a semiconductor process apparatus, and a semiconductor doping method are disclosed. The intake system includes: an intake pipe connected to the reaction chamber of the semiconductor process apparatus and guiding auxiliary ignition gas; a first control component including: a flow controller for detecting and controlling the flow rate of the auxiliary ignition gas; a first on / off valve located on the outlet side of the flow controller and controlling the opening and closing of the intake pipe; a second control component located on the outlet side of the first on / off valve and including a container for storing the auxiliary ignition gas; a second on / off valve disposed on the outlet side of the container and controlling the opening and closing of the intake pipe; the first on / off valve and the second on / off valve do not simultaneously open the intake pipe; when the second on / off valve is open, the container has a first preset pressure, and the reaction chamber has a second preset pressure lower than the first preset pressure.

Description

[Technical Field]

[0001] This application relates to the field of semiconductor equipment technology, specifically to an air intake system, semiconductor process equipment, and semiconductor doping method. [Previous Technology]

[0002] Intrinsic silicon used to manufacture wafers has very poor electrical conductivity. Only when a small amount of impurities are added to silicon to change its structure and conductivity does silicon become a useful semiconductor. This process of introducing impurities is called doping. Ion implantation is an important doping method that introduces impurities into silicon wafers by bombarding them with high-voltage ions, thereby changing the electrical properties of the silicon wafers.

[0003] In the process of preparing P-type silicon wafers, diborane (B2H6) gas is a commonly used process gas. Since B2H6 is difficult to ignite, argon (Ar) is needed to help with ignition. However, argon has an etching effect on silicon wafers. Therefore, it is necessary to ensure the stability of the process results during ion implantation. Based on this, it is necessary to quickly fill the reaction chamber with a large amount of argon gas at the beginning of the process to achieve ignition. It is also necessary to ensure the consistency of the argon gas filling parameters each time, so as to minimize the impact of argon gas on the process.

[0004] Currently, the gas inlet pipeline used to introduce argon into the reaction chamber uses a flow controller and a valve located downstream of the flow controller to jointly control the timing and volume of argon gas intake. This control method has two problems: firstly, the control delay caused by the coordination makes it impossible to accurately control the timing of gas intake; secondly, the flow control error caused by the coordination results in poor consistency of multiple gas intakes. [Summary of the Invention]

[0005] In view of this, this application provides an air intake system that enables rapid and precise air intake, and also ensures stable and controllable air intake volume and good air intake consistency, thereby improving the doping quality of silicon wafers. In addition, this application also provides a semiconductor manufacturing apparatus including the above-mentioned air intake system, and a semiconductor doping method suitable for the apparatus.

[0006] To achieve the above objectives, this application provides the following technical solution: An intake system, comprising: an intake pipe connected to a reaction chamber of a semiconductor process equipment, and used to introduce auxiliary ignition gas into the reaction chamber; a first control component disposed in the intake pipe, and comprising: a flow controller for detecting and controlling the flow rate of the auxiliary ignition gas in the intake pipe, and a first on / off valve located on the outlet side of the flow controller and controlling the opening and closing of the intake pipe; a second control component disposed in the intake pipe and located on the outlet side of the first on / off valve, and comprising: a container for storing the auxiliary ignition gas delivered from the intake pipe, and a second on / off valve disposed on the outlet side of the container and controlling the opening and closing of the intake pipe; wherein the first on / off valve and the second on / off valve do not simultaneously open the intake pipe; when the second on / off valve is open, the container has a first preset pressure, the reaction chamber has a second preset pressure, and the first preset pressure is greater than the second preset pressure.

[0007] In some embodiments, in the above-described air intake system, the ratio of the inner volume of the container to the inner volume of the reaction chamber is 1:500 to 1:300; and / or, when a predetermined amount of the auxiliary ignition gas is stored in the container and the reaction chamber is in a pre-pressurized state, the ratio of the pressure in the reaction chamber to the pressure in the container is 1:1000 to 1:500.

[0008] In some embodiments, in the above-described intake system, the flow controller is a mass flow controller, and the range of the mass flow controller is 200 sccm ~ 500 sccm.

[0009] In some embodiments, in the above-described intake system, the gas delivery distance between the second control component and the reaction chamber is less than 500 mm.

[0010] In some embodiments, in the above-described air intake system, the second control component is disposed at the air intake of the reaction chamber.

[0011] In some embodiments, in the above-described air intake system, the second control component is connected to the air intake port through an air intake structure, the air intake structure comprising: a connecting pipe, one end of which is connected to and communicates with the air intake port, and the other end is located outside the reaction chamber and communicates with the air intake pipe and the process gas delivery pipe, wherein the ratio of the inner diameter of the connecting pipe to the inner diameter of the reaction chamber is 1:5 to 2:5; a flow equalizer, disposed on the connecting pipe, and having a plurality of vent holes for gas to pass through parallel to it.

[0012] In some embodiments, in the above-described intake system, the cavity of the connecting pipe is a conical cavity, the large end of the conical cavity is connected to the intake port, and the angle between the circumferential sidewall of the conical cavity and the axis of the connecting pipe is less than 30°.

[0013] In some embodiments, in the above-described air intake system, the end of the connecting pipe away from the air intake port is a closed end, and the closed end is provided with a first air intake hole communicating with the air intake pipe and a second air intake hole communicating with the delivery pipe; and the container is disposed on the closed end.

[0014] In some embodiments, in the above-described air intake system, the container is supported on top of the closed end by a bracket so that there is a gap between the container and the closed end, and the bracket is suspended at least at the center of the closed end so that the delivery pipe can extend to the center and communicate with the second air intake hole opened at the center.

[0015] In some embodiments, in the above-described air intake system, the container includes a base fixedly mounted on the support and a barrel detachably connected to the base, wherein the inverted barrel is sealed to the base to form a storage cavity for storing the auxiliary ignition gas.

[0016] In some embodiments, in the above-described intake system, the second control component includes a pressure detection component for detecting the pressure inside the container, and a controller that is communicatively connected to the pressure detection component, the first on / off valve, and the second on / off valve. The controller controls the opening and closing of the first on / off valve and the second on / off valve based on the pressure data obtained by the pressure detection component.

[0017] A semiconductor manufacturing apparatus includes a reaction chamber and the above-described air intake system.

[0018] A semiconductor doping method, applicable to the above-mentioned semiconductor process equipment, the method comprising the following steps: when a second control component blocks the inlet pipe, a first control component is activated to allow auxiliary ignition gas to be introduced into the container of the second control component, and the first control component is closed after the pressure in the container reaches a predetermined pressure; simultaneously with the process gas entering the reaction chamber, the second control component connects the inlet pipe to the container and the reaction chamber, so that the auxiliary ignition gas stored in the container is introduced into the reaction chamber; when the pressure in the reaction chamber and / or the container reaches a constant value, the second control component blocks the inlet pipe.

[0019] In some embodiments, in the above-described semiconductor doping method, the predetermined pressure is determined using a process testing method, which includes the following steps: simultaneously introducing a process gas and an auxiliary ignition gas into the reaction chamber, wherein the amount of process gas introduced each time is consistent; each time the process gas and the auxiliary ignition gas are introduced, the amount of auxiliary ignition gas introduced and the pressure of the reaction chamber are changed to obtain the volume ratio of the auxiliary ignition gas in the reaction chamber corresponding to the stable ignition chamber pressure; and calculating the predetermined pressure according to the ideal gas law based on the ratio of the inner volume of the container to the inner volume of the reaction chamber, the stable ignition chamber pressure, and the volume ratio.

[0020] The air intake system provided in this application includes a first control component and a second control component located downstream of the first control component on the air intake pipe connecting to the reaction chamber. During the auxiliary ignition gas delivery process, the second on / off valve of the second control component first blocks the air intake pipe, and then the first control component is opened, i.e., the flow controller and the first on / off valve are switched to a connected state, so that the gas source is connected to the container of the second control component, and the auxiliary ignition gas can flow into the container of the second control component. When the amount of auxiliary ignition gas filled into the container reaches a predetermined amount, the first control component is closed. At this time, the container's... Once the pressure reaches the first preset pressure, the second on / off valve opens simultaneously with the process gas entering the reaction chamber. The pressure in the reaction chamber when the second on / off valve opens is the second preset pressure, which is less than the first preset pressure. Therefore, the auxiliary ignition gas in the container will rush into the reaction chamber under the pressure difference to help the process gas ignite. After the auxiliary ignition gas in the container is released, the second on / off valve closes again to prevent any auxiliary ignition gas from accidentally entering the reaction chamber. Then, the first control component can be turned on again to fill the container with auxiliary ignition gas for use in the next process. As can be seen from the above process, whether the auxiliary ignition gas can enter the reaction chamber can be controlled solely by the second on / off valve when the pressure in the container is greater than the pressure in the reaction chamber. It does not need to cooperate with other components. The flow controller and the first on / off valve are only used to control the filling of the container when the auxiliary ignition gas does not need to participate in the process reaction. They are unrelated to the operation of the auxiliary ignition gas entering the reaction chamber. In this way, the method of controlling the gas intake into the reaction chamber by a single component (i.e., the second on / off valve) can control the gas intake more quickly and timely. The timing of the gas intake and the amount of gas intake per intake are more precisely controlled, avoiding the occurrence of control delay and control error. The consistency of multiple gas intakes is better, which improves the doping quality of the silicon wafer.

Implementation Method

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0023] In related technologies, when preparing P-type silicon wafers using diborane (B2H6), it is necessary to achieve rapid argon gas intake into the reaction chamber. An intake pipeline for introducing argon gas into the reaction chamber uses a flow controller and a valve located downstream of the flow controller to jointly control the timing and amount of argon gas intake. That is, the flow controller controls the flow rate of argon gas entering the reaction chamber, and the opening and closing of the valve controls the start time and duration of the intake. However, in this structure, using a small-range flow controller cannot meet the requirement of rapid intake, while using a large-range flow controller results in a lag time in the opening and closing of the valve, making it difficult to control the amount of argon gas intake, i.e., there is a control delay. Furthermore, the specific intake amount needs to be determined jointly by the flow controller and the valve, and each coordination results in flow control error, leading to poor consistency across multiple intakes.

[0024] In addition, the flow controller and valve that control the opening and closing of the air intake pipeline in the above-mentioned air intake pipeline are generally installed on the gas cabinet of the semiconductor process equipment. The vertical distance between the gas cabinet and the air inlet of the reaction chamber is about 700mm. In addition, the pipeline needs to be designed to avoid bends during the actual installation, resulting in a total gas transmission length between the valve and the air inlet of the reaction chamber of more than 1500mm. Such a long transmission distance will also have a significant impact on rapid air intake.

[0025] Furthermore, the air inlet of the reaction chamber is provided with a nozzle that is connected to the air inlet pipe and is used to introduce air into the reaction chamber, as shown in Figure 1. The air intake speed of this nozzle is poor, which will also affect the rapid air intake.

[0026] In view of the above situation, as shown in Figures 2-8, this application provides an air intake system for introducing an auxiliary ignition gas for igniting the process gas into the reaction chamber 4 of a semiconductor process equipment (such as an ion implantation equipment, which mainly works by using plasma to react with silicon wafers. Under low pressure, the process gas is ionized under the excitation of radio frequency power to form plasma, and the plasma reacts with the surface of the silicon wafer to modify the electrical properties of the silicon wafer). For example, when the process gas is diborane (B2H6) or hydrogen (H2), the auxiliary ignition gas is argon (Ar).

[0027] The intake system mainly includes an intake pipe 1 and a first control component 2 and a second control component 3 installed on the intake pipe 1. The intake pipe 1 is a channel for guiding the auxiliary ignition gas; one end is connected to a gas source, and the other end is connected to a reaction chamber 4 to introduce the auxiliary ignition gas provided by the gas source into the reaction chamber 4. The first control component 2 includes a flow controller 201 and a first on / off valve 202. The flow controller 201 is used to detect and control the flow rate of the auxiliary ignition gas in the intake pipe 1. That is, the flow controller 201 can not only detect the flow rate of the auxiliary ignition gas passing through the flow controller 201, but also adjust the flow rate. Specifically, the flow controller 201... 01 can be a flow controller for detecting and controlling flow rate or a mass flow controller for detecting and controlling more precise flow rate. The first on / off valve 202 is located on the outlet side of the flow controller 201, that is, downstream of the flow controller 201 (upstream and downstream in this application are relative to the flow direction of the auxiliary ignition gas in the intake pipe 1). It can control the opening and closing of the intake pipe 1, that is, it can block and open the intake pipe 1. Since the first on / off valve 202 is located downstream of the flow controller 201, the first on / off valve 202 can also achieve the isolation between the flow controller 201 and the downstream pipes and components of the first control component 2 when blocking the intake pipe 1.The second control component 3 is located on the outlet side of the first on / off valve 202, meaning it is downstream of the first control component 2. Since the reaction chamber 4 is connected to the end of the inlet pipe 1, the second control component 3 is closer to the reaction chamber 4 than the first control component 2. In other words, the second control component 3 is located between the first control component 2 and the reaction chamber 4. By controlling the on / off state of the inlet pipe 1, the second control component 3 can also control the on / off state between the first control component 2 and the reaction chamber 4. The second control component 3 includes a container 301 and a second on / off valve 302. The container 301 is adjacent to the first on / off valve 202. When the first on / off valve 202 is open, i.e., when the first control component 2 controls the upstream portion of the inlet pipe 1 to be open, the gas source and container 301 can be connected, allowing the auxiliary ignition gas provided by the gas source to be filled into the container 301, thereby enabling the container 301 to control the auxiliary ignition gas. The storage of ignition gas involves a first on / off valve 202 closing when the auxiliary ignition gas stored in container 301 reaches a first preset pressure, thus blocking the upstream inlet pipe 1. A second on / off valve 302 is located on the outlet side of container 301, downstream of it, between container 301 and reaction chamber 4. This second on / off valve 302 also controls the opening and closing of inlet pipe 1. By opening and closing inlet pipe 1, the second on / off valve 302 enables the connection and disconnection between container 301 and reaction chamber 4. When the second on / off valve 302 needs to be opened, the first preset pressure in container 301 is greater than the second preset pressure in reaction chamber 4, creating a pressure difference. This allows the second on / off valve 302 to control whether the high-pressure auxiliary ignition gas stored in container 301 can enter the low-pressure reaction chamber 4.

[0028] When the above structure is used for control, the first on-off valve 202 and the second on-off valve 302 are not simultaneously connected to the air intake pipe 1. That is, when the first on-off valve 202 is opened to charge the auxiliary ignition gas into the container 301, the second on-off valve 302 remains closed, so that the auxiliary ignition gas will not enter the reaction chamber 4. In this way, the air intake can be controlled by the flow controller 201 and the on-off valve in the related technology. After the auxiliary ignition gas is sufficient in the container 301, the first on-off valve 202 is closed in time, so that the auxiliary ignition gas in the container 301 is no longer affected by the flow controller 201 and the first on-off valve 202. When it is necessary to input auxiliary ignition gas into the reaction chamber 4, the second on-off valve 302 can be operated alone to make the second on-off valve 302 change from the closed state. The second on / off valve 302 instantly switches to the open state. Since the auxiliary ignition gas needs to enter, the reaction chamber 4 is in a low-pressure state close to vacuum. Because the container 301 stores the auxiliary ignition gas, the container 301 has a relatively high first preset pressure, while the reaction chamber 4 has a relatively low second preset pressure. When the second on / off valve 302 connects the inlet pipe 1 to the container 301 and the reaction chamber 4, the auxiliary ignition gas in the container 301 will rush into the reaction chamber 4 under the action of pressure difference, thereby achieving rapid, timely and precise gas intake. Since the second on / off valve 302 does not cooperate with other components to control the gas intake, there will be no control delay or control error. It can not only control the timing of gas intake and the amount of gas intake at one time more accurately, but also better ensure the consistency of multiple gas intakes, thus improving the doping quality of silicon wafers.

[0029] After the auxiliary ignition gas completes its intake into the reaction chamber 4, the second on-off valve 302 closes. Then, the first control component 2 can be opened to perform the aforementioned gas filling operation into the container 301 again. This gas filling operation into the container 301 can be performed after the equipment has completed initialization and before the formal process begins, or it can be performed immediately after each time the container 301 has finished venting and the second on-off valve 302 has closed during continuous processes, or it can be performed after the previous process has ended and before the next process is about to begin. To better ensure the rapid filling effect of the auxiliary ignition gas into the reaction chamber 4, a pneumatic valve can be selected as the second on-off valve 302. Pneumatic valves have many advantages, such as rapid response, high reliability, strong environmental adaptability, convenient installation and maintenance, long service life, and low cost, which better meet the working requirements and working environment of the intake system provided in this application. Therefore, a pneumatic valve is the preferred type for the second on-off valve 302. Similarly, the first on / off valve 202 is preferably a pneumatic valve. Furthermore, to improve the performance of the intake system provided in this application, the first control component 2 includes a third on / off valve 203 and a filter 204. The function and type of the third on / off valve 203 are the same as the first on / off valve 202, and both open and close synchronously. This dual protection by the first on / off valve 202 and the third on / off valve 203 improves the reliability of the intake system. Since the first on / off valve 202 is located on the outlet side of the flow controller 201, the third on / off valve 203 is located on the inlet side of the flow controller 201. The flow controller 201 is positioned between the third on / off valve 203 and the first on / off valve 202; the filter 204 is used to filter impurities in the gas, and the filter 204 is positioned upstream of the third on / off valve 203 so that the third on / off valve 203, the flow controller 201, the first on / off valve 202, the container 301, the second on / off valve 302, and the reaction chamber 4 are all located downstream of the filter 204, thereby preventing impurities from affecting the working performance of all components such as the third on / off valve 203, the flow controller 201, the first on / off valve 202, the container 301, the second on / off valve 302, and the reaction chamber 4.

[0030] In this application, the ratio of the inner volume of container 301 to the inner volume of reaction chamber 4 is 1:500 to 1:300. To further enhance the effect of rapid gas intake, this application sets a certain ratio between the inner volume of container 301 and the inner volume of reaction chamber 4, preferably within the range of 1:500 to 1:300. This setting allows the inner volume of reaction chamber 4 to be much larger than that of container 301, enabling the auxiliary ignition gas in container 301 to enter reaction chamber 4 more fully under the pressure difference, resulting in very little residual gas in container 301. Therefore, the amount of gas remaining in container 301 can be considered minimal. The amount of gas is the same as the amount of gas entering the reaction chamber 4, thereby achieving precise control of the gas intake and improving control accuracy. On the other hand, the volume of container 301 can be reasonably set so that the single gas storage capacity of container 301 meets the single gas intake requirement, while avoiding excessive volume of container 301. This not only improves the utilization rate of internal space (preferably, after the container 301 is filled with a predetermined amount of auxiliary ignition gas, it still reserves 10% to 30% of the pressure space), but also facilitates installation and use in confined spaces, while reducing the manufacturing difficulty and cost of container 301.

[0031] When a predetermined amount of auxiliary ignition gas is stored in container 301 and reaction chamber 4 is in a pre-pressurized state, the pressure ratio between reaction chamber 4 and container 301 is 1:1000 to 1:500. This pressure ratio limitation also enhances the effect of rapid gas intake. The pre-pressurized state refers to the low-pressure state of reaction chamber 4, which is close to vacuum, when the doping process is about to begin. By maintaining this pressure ratio, not only can the pressure difference between the two be sufficiently large to allow the auxiliary ignition gas stored in container 301 to quickly rush into reaction chamber 4, but it can also be combined with the original pressure states of reaction chamber 4 and container 301 respectively, avoiding any impact on the original pressure state of reaction chamber 4. Furthermore, this pressure ratio limitation can be combined with the aforementioned limitation of the internal cavity volume ratio to further optimize the gas intake effect, or these two limitations can exist independently, i.e., only the pressure ratio or only the internal cavity volume ratio can be limited.

[0032] Furthermore, the flow controller 201 is selected as a mass flow controller, and the range of the mass flow controller is 200 sccm ~ 500 sccm. As mentioned above, the flow controller 201 can be either a flow controller or a mass flow controller, but in order to improve the air intake effect, it is preferred to use a mass flow controller with higher control accuracy. On this basis, a mass flow controller of the type with a small flow rate is also selected, that is, a mass flow controller with a range of 200 sccm ~ 500 sccm. Since the air intake volume of the auxiliary ignition gas is determined by the pressure of the container 301, the use of a small flow controller 201 can accurately control the pressure range of the container 301, ensuring that the pressure of the container 301 is basically constant (the pressure can be controlled within ±0.01 Torr), thereby making the consistency of the air intake volume of the auxiliary ignition gas better and ensuring the stability of the process.

[0033] Furthermore, the gas delivery distance between the second control component 3 and the reaction chamber 4 is less than 500 mm. The air intake system of this application also optimizes the setting position of the components, that is, the air intake system is divided into multiple parts set in different positions (the multiple parts are still connected through the air intake pipe 1), and the gas delivery distance between the second control component 3 and the air inlet 401 of the reaction chamber 4 is less than 500 mm. In this way, rapid gas filling can be achieved after the second on / off valve 302 is opened, reducing energy loss caused by excessively long pipelines and reducing the impact of gas retention in the pipe on the intake volume of auxiliary ignition gas.

[0034] Specifically, when the gas delivery distance is less than 500mm, as shown in Figure 3, the second control component 3 can be positioned at the air inlet 401 of the reaction chamber 4, i.e., the second control component 3 is positioned at the air inlet 401 of the reaction chamber 4. This minimizes the gas delivery distance between the container 301 and the second shut-off valve 302 and the reaction chamber 4, while also making fuller use of the space at the air inlet 401 of the reaction chamber 4 to install the second control component 3, resulting in more efficient space utilization. In this application, the entire air intake system is divided into two parts: one part is the second control component 3 positioned at the air inlet 401 of the reaction chamber 4, and the other part is the first control component 2, which is mounted on the gas holder 8 to minimize modifications to the relevant technology. The two parts are connected by the air intake pipe 1. Furthermore, when the first control component 2 is installed on the gas holder 8, the outlet pressure of the flow controller 201 of the first control component 2 will continue to rise because the downstream container 301 needs to be filled with gas. Therefore, a non-pressure sensitive mass flow controller needs to be selected to avoid affecting normal filling and the working performance of the mass flow controller.

[0035] As shown in Figures 3 and 4, the second control component 3 is connected to the air inlet 401 through the air inlet structure 5. The air inlet structure 5 includes a connecting pipe 501 and a flow equalizer 502. One end of the connecting pipe 501 is connected to and communicates with the air inlet 401, and the other end is located outside the reaction chamber 4 and communicates with the air inlet pipe 1 and the process gas delivery pipe 7. The flow equalizer 502 is disposed on the connecting pipe 501 and has multiple vent holes 5021 for gas to pass through in parallel. The connecting pipe 501 is a component that connects the air inlet system and the process gas delivery pipe 7 to the air inlet 401 of the reaction chamber 4. In a specific configuration, one end of the connecting pipe 501 can pass through the air inlet 401 and extend into the reaction chamber 4 and be fixedly connected to the inner wall of the reaction chamber 4. The other end of the connecting pipe 501 is outside the reaction chamber 4 and communicates with the air inlet pipe 1 and the process gas delivery pipe 7. To further shorten the air intake path, this application uses a connecting pipe 501 instead of a nozzle (or it can be understood as combining the nozzle and connecting pipe 501 into one component). A flow equalizer 502 is mounted on the connecting pipe 501. Specifically, the flow equalizer 502 can be placed inside the cavity 5011 of the connecting pipe 501, or it can be connected to the port of the connecting pipe 501 extending into the reaction chamber 4. Whether placed inside the cavity 5011 or at the port, the flow equalizer 502 is perpendicular to the axis of the connecting pipe 501, ensuring that the multiple parallel vent holes 5021 on the flow equalizer 502 flow in the same direction as the auxiliary ignition gas. This guarantees that the auxiliary ignition gas can flow normally through the vent holes 5021. Since all vent holes 5021 are arranged along the axial direction of the connecting pipe 501, these vent holes 5021 guide the flow of the auxiliary ignition gas axially, making the flow direction of each part of the auxiliary ignition gas more regular and uniform, thus improving the air intake effect. Specifically, the connection between the connecting pipe 501 and the air inlet 401, the connection between the connecting pipe 501 and the air inlet pipe 1, the connection between the connecting pipe 501 and the delivery pipe 7, and the connection between the connecting pipe 501 and the flow equalization plate 502 are all sealed by sealing rings.

[0036] In some embodiments, as shown in Figures 3 and 4, the cavity 5011 of the connecting pipe 501 is configured as a conical cavity, with the larger end of the conical cavity connected to the air inlet 401, and the angle between the circumferential sidewall of the conical cavity and the axis of the connecting pipe 501 is less than 30°. By configuring the cavity 5011 of the connecting pipe 501 as a conical cavity, the connecting pipe 501 can have a gas mixing function. When the process gas enters the connecting pipe 501 through the delivery pipe 7 and the auxiliary ignition gas enters the connecting pipe 501 through the air inlet pipe 1, the space of the conical cavity 5011 changes as the gas continues to flow. Since the gas enters from the smaller end of the connecting pipe 501 and exits from the larger end, the space of the cavity 5011 gradually increases, allowing for increasingly thorough mixing of various gases in the gradually increasing space. Specifically, as shown in Figures 3 and 4, in specific settings, only the inner cavity of the connecting pipe 501 can be set as a conical cavity, while its outer shape remains a cylindrical shape of equal diameter. Alternatively, the outer shape of the connecting pipe 501 can also be conical. Compared to the nozzle in related technologies, the conical cavity 5011 can increase the gas guiding space to 60mm~100mm, and the conical angle can be set in the range of 0~30°, thus enabling better gas mixing. The appropriate diameter, sidewall angle, etc., of the conical cavity can be selected through simulation or experimentation.

[0037] Furthermore, this application preferably uses a ratio of 1:5 to 2:5 between the inner diameter of the connecting pipe 501 (the inner cavity of the connecting pipe 501 is a conical cavity, and in this application, this inner diameter specifically refers to the inner diameter of the large opening of the conical cavity) and the inner diameter of the reaction chamber 4. For example, when the inner diameter of the reaction chamber 4 is 500 mm, the inner diameter of the connecting pipe 501 is at least 100 mm and at most 200 mm. In this way, not only does the connecting pipe 501 have a larger flow cross-sectional area, allowing argon gas to enter the reaction chamber 4 more quickly, but by setting the ratio of the inner diameter of the connecting pipe 501 to the inner diameter of the reaction chamber 4 to 1:5 to 2:5, the air intake effect can be improved, and the structural fit between the air intake system and the reaction chamber 4 can be optimized.

[0038] As shown in Figure 8, the structure obtained by combining the above-mentioned air intake system with the nozzle, when compared with the structure obtained by the nozzle alone through fluid simulation, shows that the single nozzle can make the gas flow velocity above the electrostatic chuck reach 0.75 m / s, while the structure obtained by combining the nozzle with the nozzle in this application can make the gas flow velocity above the electrostatic chuck reach 0.32 m / s. This flow velocity is less than 0.75 m / s. Therefore, the velocity uniformity of the air intake structure 5 in this application is significantly better than that of the nozzle.

[0039] In this application, as shown in Figures 3 and 4, the end of the connecting pipe 501 furthest from the air inlet 401 is a closed end 5012, and the closed end 5012 is provided with a first air inlet 503 communicating with the air inlet pipe 1 and a second air inlet 504 communicating with the conveying pipe 7; and the container 301 is disposed on the closed end 5012. Setting one end of the connecting pipe 501 as a closed end 5012 is, on the one hand, to enable it to form a platform to support the container 301, thereby realizing the placement of the container 301 on top of the connecting pipe 501; on the other hand, it makes it easier to connect and seal with the relatively small-diameter air inlet pipe 1 and conveying pipe 7, resulting in a higher degree of fit between components and a more optimized structure.

[0040] In some embodiments, as shown in Figures 3-5, the container 301 is supported on the top of the closed end 5012 by a bracket 6 so that there is a gap between the container 301 and the closed end 5012, and the bracket 6 is suspended at least at the center of the closed end 5012 so that the delivery pipe 7 can extend to the center and communicate with the second air inlet 504 opened at the center. The support 6 serves two purposes: firstly, it makes the container 301 more stable on the connecting pipe 501; secondly, by supporting the container 301 with the support 6, a gap is created between the container 301 and the closed end 5012, and the support 6 is suspended in the center of the closed end 5012. This creates a radial space extending from the outside to the center between the container 301 and the connecting pipe 501, allowing the delivery pipe 7 for conveying process gas to extend to the center. Simultaneously, the second air inlet 504 can be opened at the center of the closed end 5012, and the delivery pipe 7 can then extend axially into the second air inlet 504 to achieve communication. This allows the process gas to enter the cavity 5011 of the connecting pipe 501 from the axial part and diffuse within the cavity 5011, facilitating thorough mixing of the process gas and the auxiliary ignition gas. Specifically, container 301 is fixedly connected to tray 601 of support 6, and support leg 602 of support 6 is fastened to closed end 5012 by screws.

[0041] In some embodiments, as shown in FIG4, the container 301 includes a base 3011 fixedly mounted on the support 6, and a barrel 3012 detachably connected to the base 3011. The inverted barrel 3012 is sealed to the base 3011 to form a storage cavity for storing auxiliary ignition gas. In this application, the container 301 is configured as two parts, one part being the base 3011 and the other part being the barrel 3012. This configuration reduces the manufacturing and processing difficulty of the container 301. More importantly, it enables the container 301 to be detachable, thereby facilitating disassembly and cleaning of the container 301 during processing and use, preventing contaminating particles in the container 301 from entering the reaction chamber 4 along with the auxiliary ignition gas, which would result in excessive particle levels during the process. Specifically, the part of the barrel 3012 used for connection with the base 3011 is provided with a flange structure. When connecting, a sealing ring is provided between the two and screws are used for fastening.

[0042] When designing the flow equalizer 502, as shown in Figures 6 and 7, the vent holes 5021 can be evenly distributed on the flow equalizer 502; alternatively, the number of vent holes 5021 at the center of the flow equalizer 502 can be greater than the number at the periphery (this arrangement is not shown in the figures). The flow equalizer 502 achieves flow equalization through the vent holes 5021. When the vent holes 5021 are evenly distributed on the flow equalizer 502, sufficient flow equalization of the mixed gas can be achieved, ensuring the uniformity of the gas entering the reaction chamber 4. When the vent holes 5021 are densely distributed at the center of the flow equalizer 502, the flow equalizer 502 can perform more targeted flow equalization on the axial region of the connecting pipe 501 where the gas is relatively concentrated, thereby meeting different process requirements. In addition, other distribution methods can be used for the vent holes 5021 on the flow equalizer 502, and the specific structure can be designed with the aid of simulation.

[0043] Based on the above structure, this application further ensures that the sum of the flow cross-sectional areas of all vents 5021 is at least 60% of the plate area of ​​the flow equalizer 502. This ensures the smooth flow of process gas and auxiliary ignition gas and avoids the gas flow rate being affected by excessive flow resistance due to the setting of the flow equalizer 502.

[0044] As shown in Figure 2, the second control component 3 also includes a pressure detection component 303 for detecting the pressure inside the container 301, and a controller that is communicatively connected to the pressure detection component 303, the first on / off valve 202, and the second on / off valve 302. The controller controls the opening and closing of the first on / off valve 202 and the second on / off valve 302 based on the pressure data obtained by the pressure detection component 303. By setting the pressure detection component 303, the pressure data of the container 301 can be obtained instantly and intuitively. After transmitting this pressure data to the controller, the controller can control the opening and closing of the first on / off valve 202 and the second on / off valve 302 based on this data, thereby enabling more timely and accurate control of the amount of auxiliary ignition gas injected into the container 301, realizing automatic control of the air intake system, and improving the intelligence level of the air intake system. Specifically, the pressure detection component 303 can be a pressure gauge, pressure sensor, or other pressure sensor installed on the container 301. Alternatively, the pressure detection component 303 may be omitted, and the pressure inside the container 301 can be calculated from the flow data measured by the flow controller 201 of the first control component 2 during the process of filling the container 301 with auxiliary ignition gas.

[0045] In addition, this application embodiment also provides a semiconductor manufacturing apparatus, which includes a reaction chamber 4 and the above-mentioned air intake system. The beneficial effects of the air intake system on this semiconductor manufacturing apparatus are described above and will not be repeated here.

[0046] Based on the above-described air intake system and semiconductor process equipment, this application embodiment also provides a semiconductor doping method applicable to the above-described semiconductor process equipment. The method includes the following steps: When the second control component 3 blocks the air intake pipe 1, that is, after the equipment completes initialization or before the next process begins, the flow controller 201 and the first on / off valve 202 of the first control component 2 are opened to allow auxiliary ignition gas (e.g., argon) to be introduced into the container 301 of the second control component 3. After the pressure in the container 301 reaches a predetermined pressure, the first control component 2 is closed, and the doping process is waited for to begin. When the doping process begins, that is, at the same time as the process gas (e.g., diborane or hydrogen) enters the reaction chamber 4, the second on / off valve 302 of the second control component 3 is opened to connect the air intake pipe 1 with the container 301 and the reaction chamber 4. The auxiliary ignition gas stored in the container 301 is rushed into the reaction chamber 4 under the action of pressure difference to help the process gas ignite. When the pressure in the reaction chamber 4 and / or container 301 reaches a constant value, that is, when the pressure in container 301 and / or the pressure in the reaction chamber 4 no longer changes, the second on / off valve 302 of the second control component 3 closes to block the gas inlet pipe 1. Then, the first on / off valve 202 can be opened immediately to introduce auxiliary ignition gas into container 301, thereby preparing for the next process. The opening and closing timing of the first on / off valve 202 and the second on / off valve 302 needs to be determined according to the process conditions of the equipment and the results of the stable ignition test. After the process gas completes ignition, the process gas is continuously introduced into the reaction chamber 4 until the ion implantation of the silicon wafer is completed.

[0047] In the above steps, the predetermined pressure of container 301 is determined by a process testing method, which includes the following steps: Simultaneously introducing process gas and auxiliary ignition gas into reaction chamber 4, with the amount of process gas introduced each time being consistent; Changing the amount of auxiliary ignition gas introduced and the pressure of reaction chamber 4 each time process gas and auxiliary ignition gas are introduced, to obtain the volume ratio of auxiliary ignition gas in reaction chamber 4 corresponding to the stable ignition chamber pressure; Calculating the predetermined pressure according to the ideal gas law PV=NRT based on the ratio of the inner volume of container 301 to the inner volume of reaction chamber 4, the stable ignition chamber pressure, and the volume ratio, where P is the gas pressure, V is the gas volume, N is the amount of process gas, R is the gas constant (R=8.314Pa.m3 / (mol.K)), and T is the absolute temperature.

[0048] An example of determining the predetermined pressure of container 301 using the process testing method is as follows: When the flow rate ratio of borane to argon is 1:4 and the chamber pressure is 50mT, stable ignition can be achieved, and the ratio of argon volume to chamber volume (the inner volume of reaction chamber 4 is referred to as chamber volume) is 4 / 5; if the ratio of the inner volume of container 301 to the chamber volume is 1 / 500, then the volume ratio of argon in container 301 to argon in the chamber is 1 / 400; if all argon in container 301 is filled into reaction chamber 4, then the amount of argon N is constant. According to the ideal gas equation PV=NRT, we can obtain P1*V1=P2*V2, P2=P1*V1 / V2=50mT*400 / 1=20Torr. Therefore, when the ratio of the inner volume of container 301 to the chamber volume is 1 / 500, the predetermined pressure of container 301 is 20Torr.

[0049] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. In addition, the specific details disclosed above are only for illustrative and facilitative purposes, and are not limitations. The above details do not limit this application from having to adopt the above specific details for implementation.

[0050] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0051] It should also be noted that in the apparatus, equipment and methods of this application, each component or step can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0052] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0053] It should be understood that the qualifying terms “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and cannot be used to limit the scope of protection of this application.

[0054] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof. [Simplified Explanation of the Diagram]

[0021] To more clearly illustrate the technical solutions in the embodiments of this application 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 embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort. Figure 1 is a velocity distribution cloud diagram of the nozzle air intake in the related art; Figure 2 is a schematic diagram of the air intake system provided in the embodiment of this application; Figure 3 is a structural schematic diagram of the air intake system cooperating with the gas holder and the reaction chamber; Figure 4 is a structural schematic diagram of the second control component cooperating with the air intake structure; Figure 5 is a structural schematic diagram of the bracket; Figure 6 is a structural schematic diagram of the flow equalizer; Figure 7 is a top view of the flow equalizer; Figure 8 is a velocity distribution cloud diagram of the air intake of the air intake structure.

Claims

1. An intake system, wherein, include: An intake pipe is connected to the reaction chamber of a semiconductor manufacturing equipment and is used to introduce auxiliary ignition gas into the reaction chamber. A first control component is disposed in the air intake pipe and includes: a flow controller for detecting and controlling the flow rate of the auxiliary ignition gas in the air intake pipe, and a first on / off valve located on the outlet side of the flow controller and controlling the opening and closing of the air intake pipe; a second control component is disposed in the air intake pipe and located on the outlet side of the first on / off valve, and includes: a container for storing the auxiliary ignition gas delivered from the air intake pipe, and a second on / off valve located on the outlet side of the container and controlling the opening and closing of the air intake pipe; wherein the first on / off valve and the second on / off valve do not simultaneously open the air intake pipe; when the second on / off valve is open, the container has a first preset pressure, the reaction chamber has a second preset pressure, and the first preset pressure is greater than the second preset pressure.

2. The intake system according to claim 1, wherein, The ratio of the inner volume of the container to the inner volume of the reaction chamber is 1:500 to 1:300; and / or, when a predetermined amount of the auxiliary ignition gas is stored in the container and the reaction chamber is under pre-pressure, the ratio of the pressure in the reaction chamber to the pressure in the container is 1:1000 to 1:

500.

3. The intake system according to claim 1 or 2, wherein, The flow controller is a mass flow controller, and the flow range of the mass flow controller is 200 sccm ~ 500 sccm.

4. The intake system according to claim 1, wherein, The gas delivery distance between the second control component and the reaction chamber is less than 500 mm.

5. The intake system according to claim 1 or 4, wherein, The second control component is located at the air inlet of the reaction chamber.

6. The intake system according to claim 5, wherein, The second control component is connected to the air inlet via an air inlet structure, which includes: a connecting pipe, one end of which is connected to and communicates with the air inlet, and the other end is located outside the reaction chamber and communicates with the air inlet pipe and the process gas delivery pipe, wherein the ratio of the inner diameter of the connecting pipe to the inner diameter of the reaction chamber is 1:5 to 2:5; and a flow equalizer plate, which is disposed on the connecting pipe and has multiple vent holes for gas to pass through in parallel.

7. The intake system according to claim 6, wherein, The connecting pipe has a conical cavity, the larger end of which is connected to the air inlet, and the angle between the circumferential sidewall of the conical cavity and the axis of the connecting pipe is less than 30°.

8. The intake system according to claim 6, wherein, The end of the connecting pipe furthest from the air inlet is a closed end, and the closed end is provided with a first air inlet hole communicating with the air inlet pipe and a second air inlet hole communicating with the delivery pipe; and the container is disposed on the closed end.

9. The intake system according to claim 8, wherein, The container is supported on top of the closed end by a bracket to create a gap between the container and the closed end, and the bracket is suspended at least at the center of the closed end so that the delivery pipe can extend to the center and communicate with the second air inlet at the center.

10. The intake system according to claim 9, wherein, The container includes a base fixedly mounted on the support and a barrel detachably connected to the base. The inverted barrel is sealed to the base to form a storage chamber for storing the auxiliary ignition gas.

11. The intake system according to claim 1, wherein, The second control component includes a pressure detection component for detecting the pressure inside the container, and a controller that is communicatively connected to the pressure detection component, the first on / off valve, and the second on / off valve. The controller controls the opening and closing of the first on / off valve and the second on / off valve based on the pressure data obtained by the pressure detection component.

12. A semiconductor manufacturing apparatus, wherein, Includes a reaction chamber and an intake system as described in any one of claims 1-11.

13. A semiconductor doping method, wherein, The method, applicable to the semiconductor manufacturing apparatus of claim 12, comprises the following steps: When a second control component blocks the inlet pipe, a first control component is activated to allow auxiliary ignition gas to be introduced into the container of the second control component, and the first control component is deactivated after the pressure in the container reaches a predetermined pressure; Simultaneously with the process gas entering the reaction chamber, the second control component connects the inlet pipe to the container and the reaction chamber, allowing the auxiliary ignition gas stored in the container to be introduced into the reaction chamber; When the pressure in the reaction chamber and / or the container reaches a constant value, the second control component blocks the inlet pipe.

14. The semiconductor doping method according to claim 13, wherein, The predetermined pressure is determined using a process testing method, which includes the following steps: Simultaneously introducing a process gas and an auxiliary ignition gas into the reaction chamber, with the amount of process gas introduced consistently each time; Each time the process gas and the auxiliary ignition gas are introduced, varying the amount of auxiliary ignition gas introduced and the pressure in the reaction chamber to obtain the volume percentage of the auxiliary ignition gas in the reaction chamber corresponding to the stable ignition chamber pressure; Calculating the predetermined pressure using the ideal gas law based on the ratio of the container's internal volume to the internal volume of the reaction chamber, the stable ignition chamber pressure, and the volume percentage.

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