Gas intake control method, gas supply system and semiconductor process device

Abstract

A gas intake control method, a gas supply system and a semiconductor process device, which relate to the technical field of semiconductor processing and aim to solve the problem of the time required for gas switching being long. The gas intake control method is applied to the semiconductor process device, and comprises: obtaining a gas-holding duration, controlling a first switching valve (131) to remain closed, and controlling a second switching valve (132) to close, wherein the first switching valve (131) is connected between a mass flow meter (133) and a gas supply line of a process chamber, and the second switching valve (132) is connected between the mass flow meter (133) and an air pump (104); and after the gas-holding duration elapses, controlling the first switching valve (131) to open, and controlling the second switching valve (132) to remain closed. The gas intake control method can shorten the switching time between different gases.

Description

Air intake control method, air supply system, and semiconductor process equipment Technical Field

[0001] The present application relates to the field of semiconductor processing technology, and in particular to an air intake control method, an air supply system and semiconductor process equipment. Background Art

[0002] With the rapid development of the semiconductor industry, more sophisticated atomic layer etching and deposition have been introduced into the processing technology. At the same time, advanced packaging processes such as TSV (Through Silicon Via) have also begun to be widely used. In these semiconductor processing processes, a variety of mixed gases need to be switched quickly to achieve. For example, the Bosch process in deep silicon etching consists of a rapid switching of an etching step dominated by a fluorine-based gas and a deposition step dominated by a carbon fluorine gas. However, in the related art, the gas switching time is long and the switching frequency is low, resulting in a scallop morphology on the sidewall, which affects the product yield.

[0003] Summary of the Invention

[0004] The first purpose of the present application is to provide an air intake control method to solve the technical problem of a long time required for switching gases.

[0005] To solve the above technical problems, the present application provides an air intake control method applied to semiconductor process equipment, comprising:

[0006] Get the breath holding time,

[0007] Controlling the first switching valve to remain closed and controlling the second switching valve to close, wherein the first switching valve is connected between the mass flow meter and the gas supply line of the process chamber, and the second switching valve is connected between the mass flow meter and the air pump;

[0008] After the breath-holding time has elapsed, the first switching valve is controlled to open and the second switching valve is controlled to remain closed.

[0009] The beneficial effects of the intake control method of the present application are:

[0010] By keeping both the first and second switching valves closed, the mass flow meter is used to supply air to the gas supply line between the mass flow meter and the first and second switching valves, thereby increasing the air pressure in this area. Then, after a period of breath holding, the first switching valve is opened. Since the air pressure in this area is higher, air can be quickly supplied to the process chamber, achieving rapid ventilation and improving process performance.

[0011] In some embodiments, obtaining the breath-holding duration includes:

[0012] Obtain the volume and set flow rate of the breath-holding circuit;

[0013] The breath-holding time is obtained according to the volume of the breath-holding pipeline and the set flow rate.

[0014] In some embodiments, obtaining the breath-holding duration further includes:

[0015] Obtain breath-holding pressure and normal air pressure;

[0016] The breath-holding time is obtained according to the breath-holding pressure, the normal air pressure, the volume of the breath-holding pipeline and the set flow rate. The breath-holding time is positively correlated with the breath-holding pressure and negatively correlated with the normal air pressure.

[0017] In some embodiments, the air intake control method further includes:

[0018] The actual air pressure is obtained, and if the actual air pressure is greater than the preset air pressure, the second switching valve is controlled to open.

[0019] In some embodiments, controlling the first switching valve to remain closed and controlling the second switching valve to close includes:

[0020] Obtaining the time when gas enters the chamber;

[0021] Obtaining a breath-holding start time based on the time when the gas is introduced into the chamber and the breath-holding duration;

[0022] At the start time of the breath-holding, the first switching valve is controlled to remain closed, and the second switching valve is controlled to close.

[0023] In some embodiments, the semiconductor process equipment includes a first pipeline group and a second pipeline group, the first pipeline group is used to provide a first gas for performing a deposition process; the second pipeline group is used to provide a second gas for performing an etching process; the first pipeline group and the second pipeline group are respectively provided with the mass flow meter, the first switching valve, and the second switching valve;

[0024] During the entire deposition process, controlling the first switching valve connected to the first pipeline group to remain in an open state and the second switching valve connected thereto to remain in a closed state, so as to supply the first gas to the process chamber;

[0025] During the pre-gas holding period of the deposition process, controlling the first switching valve connected to the second pipeline group to remain in a closed state and the second switching valve connected thereto to remain in an open state, so as to disconnect the second pipeline group from the process chamber and allow the second gas to flow to the exhaust pump;

[0026] At the start of the gas holding period of the deposition process, the second switching valve connected to the second pipeline group is controlled to be closed, and remains closed until the gas holding period ends.

[0027] In some embodiments, controlling the first switching valve to remain closed and controlling the second switching valve to close further includes:

[0028] Obtaining the process duration of the deposition process preceding the etching process requiring breath holding;

[0029] The duration before breath-holding is obtained according to the process duration and the breath-holding duration, and the duration before breath-holding is positively correlated with the process duration and negatively correlated with the breath-holding duration.

[0030] The second purpose of this application is to provide a gas supply system to solve the technical problem of long time required for gas switching.

[0031] The gas supply system provided in this application is applied to semiconductor process equipment, wherein the semiconductor process equipment includes a process chamber. The gas supply system is used to perform the above-mentioned gas intake control method provided in this application, and the gas supply system includes:

[0032] Gas supply lines, each of the gas supply lines being independently connected to the process chamber via a first switching valve;

[0033] An air extraction pump, each of the air supply lines is independently connected to the air extraction pump via a second switching valve;

[0034] a mass flow meter, wherein the air supply path is connected to the first switching valve and the second switching valve via the mass flow meter; and

[0035] A check control component is used to prevent the air pressure on the side of the mass flow meter facing the first switching valve and the second switching valve from being higher than the air pressure on the side of the mass flow meter facing the air supply path.

[0036] By setting up a non-return control component, the gas in the holding air pipeline between the first switching valve and the second switching valve can be discharged when the holding air pressure is too high during holding air in the air supply pipeline, thereby eliminating the risk of failure of the mass flow meter and even the gas duct due to excessive air pressure in the holding air pipeline between the mass flow meter and the first switching valve and the second switching valve due to the holding time being too long.

[0037] In some embodiments, the check control assembly includes a vacuum gauge, which is used to measure the air pressure of the pipeline between the mass flow meter and the first switching valve or between the mass flow meter and the second switching valve.

[0038] In some embodiments, the check control assembly further includes a one-way valve, which is disposed between the air pump and the mass flow meter; the one-way valve is configured to conduct only one-way flow from the mass flow meter to the air pump.

[0039] In some embodiments, the gas supply system further comprises a controller, wherein the controller comprises:

[0040] Acquisition module, used to obtain breath-holding duration;

[0041] a first control module, configured to control a first switching valve to remain closed and to control a second switching valve to close, wherein the first switching valve is connected between a mass flow meter and a gas supply line of a process chamber, and the second switching valve is connected between the mass flow meter and a vacuum pump; and

[0042] The second control module is used to control the first switching valve to open and the second switching valve to close after the breath-holding time has expired.

[0043] The third object of the present application is to provide a semiconductor process equipment to solve the technical problem of the long time required for switching gases.

[0044] The semiconductor process equipment provided in this application includes the above-mentioned gas supply system provided in this application.

[0045] By arranging the above-mentioned gas supply system in the semiconductor process equipment, the semiconductor process equipment accordingly has all the advantages of the above-mentioned gas supply system, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments or background technologies of the present application, the following briefly introduces the drawings required for use in the embodiments or background technology descriptions. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0047] FIG1 is a schematic diagram of a process chamber of a semiconductor process equipment to which an intake control method provided by an embodiment of the present application is applied;

[0048] FIG2 is a schematic diagram of a gas supply system of a semiconductor process equipment to which an air intake control method provided by an embodiment of the present application is applied;

[0049] 3 is a schematic diagram of a sub-gas supply circuit in a gas supply system of a semiconductor process equipment to which an intake control method provided by an embodiment of the present application is applied;

[0050] FIG4 is a schematic flow chart of an intake control method provided in one embodiment of the present application;

[0051] FIG5 is a comparative schematic diagram of gas state switching in a related art 1 and an embodiment of the present application;

[0052] FIG6 is a schematic diagram of the control flow of the first switching valve and the second switching valve in one embodiment of the related art 1 and the present application;

[0053] FIG7 is a timing diagram showing a comparison of the flow rate of air entering a process chamber from a certain edge air inlet pipe in a related art 1 and an embodiment of the present application;

[0054] FIG8 is a schematic diagram of air pressure changes in a process chamber when an edge air inlet pipe is used to supply air to the process chamber in accordance with a related art 1 and an embodiment of the present application;

[0055] FIG9 is a flow chart of an intake control method according to an embodiment of the present application;

[0056] FIG10 is a schematic structural diagram of a controller in an air supply system according to an embodiment of the present application.

[0057] Description of reference numerals:

[0058] 101- central air inlet; 102- edge air inlet; 103- molecular pump; 104- air pump;

[0059] 110 - first pipeline group; 111 - first sub-gas path; 112 - second sub-gas path; 113 - third sub-gas path; 120 - second pipeline group;

[0060] 131 - first switching valve; 132 - second switching valve; 133 - mass flow meter; 134 - vacuum gauge;

[0061] 401 - acquisition module; 402 - first control module; 403 - second control module; 404 - pressure relief module. DETAILED DESCRIPTION

[0062] Related technology 1:

[0063] This related art provides a gas switching system for supplying different gases to a chamber (e.g., a plasma processing chamber of a plasma processing apparatus). The chamber may include multiple zones, and the gas distribution system can distribute different gases to the multiple zones. The gas switching system can selectively supply one or more gases to the chamber, while supplying the remaining gases to a bypass line.

[0064] However, this technology limits the intake air flow rate to the set flow rate of the MFC (mass flow controller), which may not be suitable for applications with large intake air flows. Furthermore, the gas that does not enter the chamber is pumped away through the bypass line, resulting in gas waste.

[0065] Related technology 2:

[0066] This related technology discloses a plasma reaction chamber and method for achieving rapid switching of reaction gases. Two groups of gases are injected into the reaction chamber from the top and bottom of the reaction chamber at the same time. While ensuring that the etching reaction and deposition reaction of the substrate are not affected, the volume of the reaction chamber is reduced in disguise, which is more conducive to the rapid filling of the reaction chamber by the gas, thereby increasing the switching rate of the etching step and the deposition step, and thus increasing the etching rate of the substrate.

[0067] However, in the aforementioned related art, while injecting process gas from the top of the reaction chamber, in order to maintain a consistent total gas flow rate throughout the entire process and thus stabilize the reaction chamber pressure, gases not used in this step are simultaneously directed to the lower portion of the reaction chamber, thereby effectively reducing the reaction chamber volume. However, this intake method requires specially designed piping to direct gases not used in this step to the lower portion of the reaction chamber, which can affect the airflow field within the reaction chamber. Furthermore, this solution can cause the process gas to constantly mix with gases not used in this step, negatively impacting the process results.

[0068] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0069] Figure 1 is a schematic diagram of a process chamber of a semiconductor process equipment to which the air intake control method provided by an embodiment of the present application is applied; Figure 2 is a schematic diagram of a gas supply system of a semiconductor process equipment to which the air intake control method provided by an embodiment of the present application is applied; as shown in Figures 1 and 2, the semiconductor process equipment includes a process chamber, the process chamber having a central air inlet 101 located at the center of its top, the central air inlet 101 being connected to a central air inlet pipeline, and the process chamber also having an edge air inlet 102 located on its side wall, the edge air inlet 102 being connected to an edge air inlet pipeline. The gas supply system for semiconductor processing equipment includes a first pipeline group 110 and a second pipeline group 120. The first pipeline group 110 includes a first sub-gas path 111 for supplying SF6, a second sub-gas path 112 for supplying NF3, and a third sub-gas path 113 for supplying O2. Each sub-gas path is provided with a corresponding mass flowmeter 133. Specifically, the first sub-gas path 111 is provided with MFC01; the second sub-gas path 112 is provided with MFC02; and the third sub-gas path 113 is provided with MFC03. The first, second, and third sub-gas paths 111, 112, and 113 are connected to the upstream ends of a first switching valve 131 and a second switching valve 132. The downstream end of the first switching valve 131 is connected to the edge air inlet pipeline (i.e., "To Edge" in FIG. 2). The downstream end of the second switching valve 132 is connected to the vacuum pump 104. When the second switching valve 132 is turned on, the vacuum pump 104 can extract the gas supplied by the first sub-gas path 111, the second sub-gas path 112 and the third sub-gas path 113; the second pipeline group 120 includes a gas path that can supply C4F8 gas, and a mass flow meter 133, namely MFC04, is also provided on the gas path of the second pipeline group 120. In the second pipeline group 120, one end of the downstream side of the mass flow meter 133 is connected to the edge air inlet pipeline (i.e., To Edge in Figure 2) through another first switching valve 131, and is connected to the vacuum pump 104 through another second switching valve 132.

[0070] FIG4 is a schematic flow chart of an air intake control method provided by one embodiment of the present application. As shown in FIG4 , the air intake control method can be applied to the above-mentioned semiconductor process equipment, and the method includes:

[0071] S210, obtain breath-holding time;

[0072] The above step S210 specifically includes:

[0073] S211, obtaining the volume and set flow rate of the breath-holding pipeline;

[0074] Among them, the breath-holding pipeline refers to the pipeline from the mass flowmeter 133 to the first switching valve 131 and the second switching valve 132 in the first sub-gas path 111, the second sub-gas path 112 and the third sub-gas path 113. Correspondingly, the volume of the breath-holding pipeline refers to the sum of the volumes of the internal spaces of the pipeline between the mass flowmeter 133 and the first switching valve 131 and the second switching valve 132. The set flow rate refers to the flow rate controlled by the corresponding mass flow meter 133 when various gases flow. The volume of the breath-holding pipeline is usually 10ml~5L. In this embodiment, the use step time of each gas is usually 0.1s~10s. Correspondingly, the breath-holding time is usually less than 5s.

[0075] S212. Obtain the breath-holding duration based on the volume of the breath-holding pipeline and the set flow rate:

[0076] Specifically, the breath-holding time can be obtained by dividing the volume of the breath-holding pipeline by the set flow rate.

[0077] Of course, considering that the breath-holding pressure is higher than the normal pressure, the above step S210, i.e., obtaining the breath-holding time, further includes:

[0078] Obtain breath-holding pressure and normal air pressure;

[0079] The breath-holding time is obtained based on the breath-holding pressure, normal air pressure, the volume of the breath-holding pipeline and the set flow rate. The breath-holding time is positively correlated with the breath-holding pressure and negatively correlated with the normal air pressure.

[0080] Among them, the normal air pressure is the air pressure when various gases are introduced into the central air inlet line or the edge air inlet line, or after entering the process chamber. The holding air pressure is the highest air pressure during the holding process. Since the holding air pressure is greater than the normal air pressure, it means that during the holding process, the amount of gas entering the holding line is greater than the amount of gas flowing normally in the holding line, so a longer holding time is required. Therefore, the relationship between the holding air pressure and the normal air pressure needs to be taken into account. The holding air pressure is the maximum air pressure during the holding process, not the average air pressure during the holding process. Therefore, the holding time is positively correlated with the holding air pressure, and negatively correlated with the normal air pressure, and is not directly calculated by dividing the holding air pressure by the normal air pressure. For example, if the normal air pressure is 100mT and the breath-holding pressure is 200mT, when calculating the breath-holding time, instead of simply dividing the volume of the breath-holding circuit by the set flow rate and multiplying the result by 2, you can consider multiplying it by a correction factor of 1.5 or 1.6 to obtain a more reliable breath-holding time.

[0081] S220 , controlling the first switching valve 131 to remain closed, and controlling the second switching valve 132 to close.

[0082] In some embodiments, the above step S220 specifically includes:

[0083] Obtaining the time when gas enters the chamber;

[0084] The breath-holding start time is obtained based on the time when the gas is introduced into the chamber and the breath-holding duration;

[0085] At the breath-holding start time, the first switching valve 131 is controlled to remain in the closed state, and the second switching valve 132 is controlled to be closed.

[0086] Specifically, the moment when each gas enters the chamber is obtained, and based on the moment when the gas enters the chamber, the breath-holding duration is reversed to obtain the breath-holding start moment, that is, the time point when the breath-holding starts. At this time point, the second switching valve 132 is controlled to switch from the previous open state to the closed state, and the first switching valve 131 is controlled to remain in the closed state.

[0087] In this embodiment, the semiconductor process equipment includes a first pipeline group 110 and a second pipeline group 120. The first pipeline group 110 is used to provide a first gas for performing a deposition process; the second pipeline group 120 is used to provide a second gas for performing an etching process; the first pipeline group 110 and the second pipeline group 120 are respectively provided with a mass flow meter 133, a first switching valve 131 and a second switching valve 132;

[0088] Especially in the Bosch process, deposition steps and etching steps are required, and different gases are introduced alternately. Since the etching rate is related to pressure, a higher gas pressure will lead to a higher etching rate. However, the mixing state of the gas will also reduce the wafer production capacity. At the same time, a lower deposition pressure will make the deposition more uniform, especially for the side wall protection of the countersunk hole, which requires a lower gas pressure. Therefore, most of the time, the process recipe is as shown in Table 1 below. There is a low-pressure deposition step and two high-pressure etching steps in one cycle. The deposition step requires gas supply from the first pipeline group 110, and the two etching steps require gas supply from the second pipeline group 120. Therefore, there are two gas supply line switches in one cycle.

[0089] Table 1

[0090] As can be seen from Table 1 above, the pressure in the process chamber increases when switching from a deposition step to an etching step. Conversely, there is a pressure drop when switching from an etching step to a deposition step. Therefore, when switching from a deposition process to an etching process, it is necessary to hold the gas supply line when introducing the gas required for the etching process into the process chamber. However, when switching from an etching process to a deposition process, holding the gas is not necessary.

[0091] Based on this, during the entire process of executing the deposition process, the first switching valve 131 connected to the first pipeline group 110 is controlled to remain in an open state, and the second switching valve 132 connected to it is controlled to remain in a closed state, so as to provide the first gas to the process chamber; during the pre-holding time of the deposition process (pre-holding time = deposition process time - holding time), the first switching valve 131 connected to the second pipeline group 120 is controlled to remain in a closed state, and the second switching valve 132 connected to it is controlled to remain in an open state, so as to disconnect the second pipeline group 120 from the process chamber and allow the second gas to pass to the vacuum pump 104; at the start time of the holding time of the deposition process, the second switching valve 132 connected to the second pipeline group 120 is controlled to close, and remain closed until the end of the holding time, thereby achieving holding time within the holding time of the deposition process.

[0092] The specific method for obtaining the holding time of the deposition process is, for example, as follows: the above-mentioned step S220, i.e., controlling the first switching valve 131 to remain closed and controlling the second switching valve 132 to be closed, further comprising:

[0093] Obtaining the process duration of the deposition process;

[0094] The pre-breathing time is obtained based on the deposition process duration and the breath-holding time. The pre-breathing time is positively correlated with the deposition process duration and negatively correlated with the breath-holding time. Specifically, the pre-breathing time = the deposition process duration - the breath-holding time.

[0095] During the pre-hold period, the first switching valve 131 connected to the first pipeline group 110 remains open, while the second switching valve 132 remains closed, allowing the first gas used in the deposition process to flow into the process chamber. Meanwhile, during the pre-hold period, the first switching valve 131 connected to the second pipeline group 120 remains closed, while the second switching valve remains open, allowing the second gas used in the etching process to flow into the vacuum pump 104.

[0096] During the subsequent holding period, the states of the first switching valve 131 and the second switching valve 132 connected to the first pipeline group 110 remain unchanged, and the first gas continues to flow into the process chamber; at the beginning of the holding period, the first switching valve 131 connected to the second pipeline group 120 is closed and remains closed until the end of the holding period, and the second switching valve 132 remains closed, and the second gas flows into the holding pipeline and holds the breath.

[0097] When the hold time ends, i.e., when the etching process gas is introduced into the chamber, the first switching valve 131 connected to the first pipeline group 110 is closed, and the second switching valve 132 connected thereto is opened, allowing the first gas to be introduced to the vacuum pump 104 and maintained there until the deposition process begins again. The first switching valve 131 connected to the second pipeline group 120 is opened, and the second switching valve 132 connected thereto is closed, allowing the second gas to be introduced into the process chamber until the etching process is completed.

[0098] Therefore, in this embodiment, the opening and closing of the first switching valve 131 and the second switching valve 132 in the pipeline group supplying gas to perform a certain process are not synchronized. This "non-synchronization" means that when one of the first switching valve 131 and the second switching valve 132 in the pipeline group is opened, the other does not simultaneously close. In actual operation, the first switching valve 131 in the pipeline group will initially remain closed, while the corresponding second switching valve 132 opens for a period of time during this period. It will then close again to achieve the required breath-holding time, and then the first switching valve 131 will be opened again to achieve pressure boosting.

[0099] S230 , obtaining the actual air pressure. If the actual air pressure is greater than the preset air pressure, controlling the second switching valve 132 to open.

[0100] As shown in Figure 3, the actual air pressure refers specifically to the gas pressure in the hold-air pipeline. Since both the first switching valve 131 and the second switching valve 132 remain closed during the hold-air process, the air pressure in the hold-air pipeline can be considered to be essentially uniform. Specifically, the actual air pressure can be measured by a vacuum gauge connected to the hold-air pipeline. The preset air pressure is the maximum pressure allowed in the hold-air pipeline, which can be, for example, 1 torr to 760 torr. When the actual air pressure exceeds the preset pressure, the second switching valve 132 can be forced open to allow the gas to escape and an alarm can be triggered. Since the vacuum pump 104 is connected to the molecular pump 103, a pressure of 400 torr here will generally not harm the vacuum system. In this solution, a hold-air pressure of less than 400 torr is used to supply gas to the process chamber. Without this control step, the pressure in the hold-air pipeline would continue to rise as the hold-air time increases, ultimately causing the mass flowmeter 133 to fail and creating the risk of backflow. By adopting this control method, it is possible to ensure that the downstream side of the mass flow meter 133 is in a safe air pressure state, thereby preventing the mass flow meter 133 from failing.

[0101] S240: After the breath-holding time has elapsed, the first switching valve 131 is controlled to open and the second switching valve 132 is controlled to remain closed.

[0102] In the above step S240, the start time of the above breath-holding time is calculated from the time when the first switching valve 131 is controlled to remain in the closed state and the second switching valve 132 is controlled to be closed.

[0103] If the actual duration of holding the breath is too long, the air pressure on both sides of the mass flowmeter 133 will be the same, causing the mass flowmeter 133 to fail. Therefore, during the holding breath process, the air pressure continues to rise. When the holding breath time is reached, that is, after the holding breath time has passed, the first switching valve 131 is controlled to open and the second switching valve 132 is closed. The gas with a higher air pressure in the holding breath pipeline, that is, the gas with a larger amount of substance, can enter the edge air inlet pipeline. Therefore, at the beginning of the process step, the actual air intake flow rate is greater than the set flow rate of the mass flowmeter 133. For example, in this embodiment, holding the breath for 0.3s can instantly increase the pressure rise rate of the process chamber by two times, which is significantly higher than the conventional method. In the conventional method, the usual air intake rate is 20sccm to 3000sccm, preferably 100sccm to 600sccm. Therefore, the present application adopts the above-mentioned air intake control method to complete the gas exchange faster. If multiple groups of mixed gases are used to react alternately during the process, this process can realize a process of rapid gas switching.

[0104] In summary, the present application adopts the above-mentioned holding time before a certain process gas enters the chamber (i.e., at the start of holding), closes the second switching valve, and first continuously introduces the process gas into the holding pipeline, so that holding occurs in the holding pipeline, which can effectively increase the air pressure in the holding pipeline. Since the rate at which the gas flows through a certain section of the pipeline or a certain area is positively correlated with the pressure difference between the inlet and outlet ends of this section of the pipeline or this area, the air pressure in the holding pipeline is increased, which can significantly increase the rate at which the process gas enters the process chamber through the first switching valve. In other words, for the same amount of gas entering, the intake time can be shortened, that is, the intake efficiency is improved.

[0105] Moreover, since the second switching valve is closed before the gas is introduced into the chamber, unlike the solution in the related art where part of the gas introduced is pumped away, the process gas introduced before the gas introduction can enter the process chamber without being directly pumped away by the pump, which can also save the amount of process gas. In addition, if the air pressure of the process chamber is different in different process steps, when the air pressure of the latter process step is higher than that of the former process step, holding the air in the air holding line can increase the air pressure in the air holding line, so as to facilitate reaching the air pressure of the process chamber in advance during the process of introducing air into the process chamber, which can shorten the time for the process chamber to reach the air pressure.

[0106] In addition, Figure 5 is a comparative schematic diagram of the gas state switching between the related technology 1 and the embodiment of the present application. The upper half of the figure is the related technology 1, and the lower half is the embodiment of the present application. Figure 6 is a control flow diagram of the first switching valve 131 and the second switching valve 132 in the related technology 1 and the embodiment of the present application. The left half of the figure is the related technology 1, and the right half is the embodiment of the present application. Figure 7 is a comparative timing diagram of the flow rate of air entering the process chamber from a certain edge air inlet pipe in the related technology 1 and the embodiment of the present application. The upper half of the figure is the related technology 1, and the lower half is the embodiment of the present application. Figure 8 is a schematic diagram of the air pressure change in the process chamber when air is entering the process chamber from a certain edge air inlet pipe in the related technology 1 and the embodiment of the present application; the left half of the figure is the related technology 1, and the right half is the embodiment of the present application.

[0107] In the solution using related art 1, at time 2 in Figure 7 , the gas passing through the mass flow meter 133 at a set flow rate does not enter the process chamber to participate in the process, but is instead extracted by the vacuum pump 104, resulting in gas waste. In the embodiment of the present application, however, some or all of the gas that would otherwise be extracted by the vacuum pump 104 is stored between the mass flow meter 133 and the first switching valve 131. At the beginning of the process step, it is quickly introduced into the process chamber to participate in the process. Therefore, this method can save process gas, that is, use a smaller flow rate to complete the gas switching.

[0108] When there is a large pressure differential between steps, for example, when the high-pressure step is more than 30 mT higher than the step with the lowest pressure, this intake method, by increasing the pressure in the hold-in line, can increase the pressure upstream of the first switching valve 131, which is needed to admit air into the process chamber at the beginning of the process step. This can accelerate the intake rate, quickly complete the gas exchange within the process chamber, and increase the pressure to prevent the two gas groups from mixing for a long time within the process chamber, thereby improving process performance. As shown in Figure 5, in Figure 5, during each "opening to the chamber" process to the right of "closing 132" (i.e., closing the second switching valve 132), the aforementioned intake enhancement phase, which accelerates the intake rate, occurs. That is, each time the second switching valve 132 is closed and then the first switching valve 131 is opened, the gas exchange within the process chamber is completed more quickly. The duration of the intake enhancement phase can be the entire duration of the intake of air into the process chamber or the beginning of the duration of the intake of air into the process chamber. The entire duration is shown in the dotted triangle portion in the lower half of Figure 7.

[0109] For example, at the beginning of a deposition step, the duration of that step and the holding time for the next step are read. At the start of the holding time before the end of the deposition step, the second switching valve 132 for the gas required for the next step is closed, and the gas required for the next step is held. This allows for a faster pressure increase rate when the process chamber requires a higher pressure at the start of the next step. As shown in FIG8 , the left figure shows the ultimate pressure rise curve for 500 sccm of SF6 when this control method is not used. The first switching valve 131 is opened, and the time for gas to enter the process chamber is 1.4 seconds, resulting in a pressure increase of 158 mT. The right figure shows the ultimate pressure rise curve for 500 sccm of SF6 when a control method with a holding function is used. This shows that a pressure increase of 150 mT can be achieved when the first switching valve 131 is opened and the time for gas to enter the process chamber is 0.5 seconds. The pressure increase rate is nearly three times that of when this control method is used. This results in higher etch rates and wafer throughput. In Table 1 above, when transitioning from the second etching step to the deposition step, the existing gas flow method can be used because a high pressure increase is not required. In actual applications, the process recipe is not limited to the three steps and two gas flow conditions shown in Table 1.

[0110] FIG9 is a schematic flow chart of another intake control method according to an embodiment of the present application, the method comprising:

[0111] S301. Obtain the volume, set flow rate, breath-holding pressure, and normal pressure of the breath-holding circuit.

[0112] S302: Obtain the breath-holding time according to the breath-holding pressure, the normal air pressure, the volume of the breath-holding pipeline, and the set flow rate.

[0113] S303, obtaining the time when the gas enters the chamber, and obtaining the start time of breath holding according to the time when the gas enters the chamber and the breath holding duration, and controlling the first switching valve 131 to remain closed at the start time of breath holding, and controlling the second switching valve 132 to close.

[0114] S304, obtaining actual air pressure;

[0115] S305: If the actual air pressure is greater than the preset air pressure, the second switching valve 132 is controlled to open;

[0116] S306 , after the breath-holding time has elapsed, control the first switching valve 131 to open and the second switching valve 132 to close.

[0117] The present application also provides a gas supply system for use in semiconductor process equipment, wherein the semiconductor process equipment includes a process chamber. The gas supply system is configured to execute the aforementioned gas intake control method. The gas supply system includes:

[0118] Gas supply lines, each gas supply line is independently connected to the process chamber through a first switching valve 131;

[0119] The air pump 104, each air supply path is independently connected to the air pump 104 through the second switching valve 132;

[0120] A mass flow meter 133 , through which the air supply path is connected to the first switching valve 131 and the second switching valve 132 ; and

[0121] The non-return control component is used to prevent the air pressure on the side of the mass flow meter 133 facing the first switching valve 131 and the second switching valve 132 from being higher than the air pressure on the side of the mass flow meter 133 facing the air supply path.

[0122] Specifically, in the semiconductor process equipment used in this embodiment, the upstream of the molecular pump 102 is connected to the process chamber, and the downstream of the molecular pump 102 is connected to the exhaust pump 104. The molecular pump 102 can extract the gas in the process chamber and discharge it through the exhaust pump 104.

[0123] In this embodiment, the gas supply line is independently connected to the process chamber through the first switching valve 131, which means that the gas required to be introduced when performing each process is connected to the process chamber through a first switching valve 131. For example, the gas introduced into the process chamber when performing the etching process is connected to the process chamber through a first switching valve 131, and the gas introduced into the process chamber when performing the deposition process is connected to the process chamber through another first switching valve 131. Connecting to the process chamber through the first switching valve 131 does not mean that the outlet of the first switching valve 131 is directly connected to the process chamber, but that the first switching valve 131 is connected to the process chamber through an air inlet line. The air inlet line may include a central air inlet line for leading to the top of the process chamber and an edge air inlet line for leading to the side wall of the process chamber.

[0124] By setting up a check control component, when holding air in the air supply pipeline, the gas in the holding air pipeline between the first switching valve 131 and the second switching valve 132 can be discharged when the holding air pressure is too high, thereby eliminating the risk of failure of the mass flow meter or even backflow of gas due to excessive air pressure in the holding air pipeline between the mass flow meter 133 and the first switching valve 131 and the second switching valve 132 due to the holding air time being too long.

[0125] In some embodiments, as shown in FIG3 , the check control assembly includes a vacuum gauge 134 , which is used to measure the air pressure in the pipeline between the mass flow meter 133 and the first switching valve 131 or between the mass flow meter 133 and the second switching valve 132 .

[0126] Specifically, in this embodiment, the range of the vacuum gauge 134 can be selected to be 1 torr to 760 torr. Since in the semiconductor process equipment used in this embodiment, the process chamber is connected to the molecular pump 102, and the molecular pump 102 is connected to the exhaust pump 104, and the holding air pressure in this embodiment is less than 400 torr, the pressure here below 400 torr will not cause damage to the vacuum system.

[0127] By setting the vacuum gauge 134 , the air pressure of the breath-holding pipeline between the first switching valve 131 and the second switching valve 132 can be obtained. When the air pressure exceeds the preset air pressure, the relevant valves can be controlled to operate, thereby protecting the mass flow meter 133 .

[0128] In some embodiments, the check control assembly further includes a one-way valve (not shown in the figure), which is arranged between the air pump 104 and the mass flow meter 133; the one-way valve is configured to only conduct one-way flow from the mass flow meter 133 to the air pump 104.

[0129] By setting a one-way valve, the gas at the inlet of the vacuum pump 104 can be prevented from flowing back to the downstream side of the mass flow meter 133, and the gas discharged from the process chamber in the previous step can be prevented from flowing into the process chamber again through the first switching valve 131 when the gas supply system is running, thereby ensuring the reliability of the process operation.

[0130] FIG10 is a schematic structural diagram of a controller in an air supply system according to an embodiment of the present application.

[0131] As shown in FIG10 , the gas supply system further includes a controller, which includes:

[0132] An acquisition module 401 is used to obtain a breath-holding duration;

[0133] The first control module 402 is used to control the first switching valve 131 to remain closed and the second switching valve 132 to close. The first switching valve 131 is connected between the mass flow meter 133 and the gas supply line of the process chamber, and the second switching valve 132 is connected between the mass flow meter 133 and the air pump 104.

[0134] The second control module 403 controls the first switching valve 131 to open and the second switching valve 132 to close after the breath-holding time has elapsed.

[0135] As an embodiment, the acquisition module 401 is specifically used to: obtain the volume and set flow rate of the breath-holding pipeline, and obtain the breath-holding time according to the volume and set flow rate of the breath-holding pipeline.

[0136] As an embodiment, the acquisition module 401 is also specifically used to: obtain the breath-holding pressure and the normal air pressure, and obtain the breath-holding time according to the breath-holding pressure, the normal air pressure, the volume of the breath-holding pipeline and the set flow rate. The breath-holding time is positively correlated with the breath-holding pressure and negatively correlated with the normal air pressure.

[0137] As an embodiment, the controller further includes a pressure relief module 404 , which is specifically configured to obtain actual air pressure, and if the actual air pressure is greater than a preset air pressure, control the second switching valve 132 to open.

[0138] As an embodiment, the second control module 403 is further specifically used to obtain the time when the gas enters the chamber, and obtain the start time of holding the breath based on the time when the gas enters the chamber and the duration of holding the breath; at the start time of holding the breath, the first switching valve 131 is controlled to remain closed, and the second switching valve 132 is controlled to be closed.

[0139] As an embodiment, the second control module 403 is further specifically configured to control the first switching valve 131 to remain closed and control the second switching valve 132 to close, including:

[0140] Obtain the process duration of the deposition process, and obtain the pre-breath-holding time based on the process duration of the deposition process and the breath-holding time. The pre-breath-holding time is positively correlated with the deposition process duration and negatively correlated with the breath-holding time.

[0141] After the deposition process starts and the holding time has passed, the second switching valve 132 is controlled to be closed.

[0142] An embodiment of the present application further provides a conductor processing device, comprising the above-mentioned gas supply system.

[0143] By arranging the above-mentioned gas supply system in the semiconductor process equipment, the semiconductor process equipment accordingly has all the advantages of the above-mentioned gas supply system, which will not be described in detail here.

[0144] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be based on the scope defined by the claims.

[0145] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0146] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from the other embodiments. Similar or identical parts between the various embodiments can be referred to in conjunction with each other. Regarding the air conditioner control device and air conditioner disclosed in the embodiments, since they correspond to the air conditioner control method disclosed in the above embodiments, the description is relatively simple. For relevant details, refer to the method description.

[0147] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be based on the scope defined by the claims.

Claims

1. An air intake control method, applied to semiconductor process equipment, characterized in that: include: Get the breath holding time. Controlling the first switching valve to remain in a closed state, and controlling the second switching valve to close, wherein the first switching valve is connected between the mass flow meter and the gas supply pipeline of the process chamber, and the second switching valve is connected between the mass flow meter and the air pump; After the breath-holding time has elapsed, the first switching valve is controlled to open and the second switching valve is controlled to remain closed.

2. The air intake control method according to claim 1, characterized in that: The breath-holding time obtained includes: Obtain the volume and set flow rate of the breath-holding circuit; The breath-holding time is obtained according to the volume of the breath-holding pipeline and the set flow rate.

3. The intake air control method according to claim 2, characterized in that: The obtaining of the breath-holding duration also includes: Obtain breath-holding pressure and normal air pressure; The breath-holding time is obtained according to the breath-holding air pressure, the normal air pressure, the volume of the breath-holding pipeline and the set flow rate, and the breath-holding time is positively correlated with the breath-holding air pressure and negatively correlated with the normal air pressure.

4. The intake air control method according to claim 1, characterized in that: The air intake control method further includes: The actual air pressure is obtained, and if the actual air pressure is greater than the preset air pressure, the second switching valve is controlled to open.

5. The intake air control method according to claim 1, characterized in that: The controlling the first switching valve to remain in a closed state and controlling the second switching valve to close includes: Obtaining the time when gas is introduced into the chamber; Obtaining a breath-holding start time according to the time when the gas is introduced into the chamber and the breath-holding duration; At the start time of the breath-holding, the first switching valve is controlled to remain in a closed state, and the second switching valve is controlled to be closed.

6. The intake air control method according to claim 1, characterized in that: The semiconductor process equipment comprises a first pipeline group and a second pipeline group, wherein the first pipeline group is used to provide a first gas for performing a deposition process; The second pipeline group is used to provide a second gas for performing an etching process; the first pipeline group and the second pipeline group are respectively provided with the mass flow meter, the first switching valve and the second switching valve; During the entire process of performing the deposition process, controlling the first switching valve connected to the first pipeline group to remain in an open state and the second switching valve connected thereto to remain in a closed state, so as to provide the first gas to the process chamber; During the pre-gas holding time of the deposition process, the first switching valve connected to the second pipeline group is controlled to remain in a closed state, and the second switching valve connected to the second pipeline group is controlled to remain in an open state, so that the second pipeline group is disconnected from the process chamber and the second gas is passed to the exhaust pump; At the start time of the gas holding period of the deposition process, the second switching valve connected to the second pipeline group is controlled to be closed, and remains closed until the gas holding period ends.

7. The intake air control method according to claim 6, characterized in that: The controlling the first switching valve to remain in a closed state and controlling the second switching valve to close further includes: Obtaining the process duration of the deposition process before the etching process that requires holding breath; The time before breath-holding is obtained according to the process time and the breath-holding time, and the time before breath-holding is positively correlated with the process time and negatively correlated with the breath-holding time.

8. A gas supply system, applied to semiconductor process equipment, wherein the semiconductor process equipment comprises a process chamber, characterized in that: The air supply system is used to execute the air intake control method according to any one of claims 1 to 7, and the air supply system comprises: Gas supply lines, each of which is independently connected to the process chamber via a first switching valve; An air pump, each of the air supply lines is independently connected to the air pump via a second switching valve; a mass flow meter, wherein the gas supply path is connected to the first switching valve and the second switching valve through the mass flow meter; and A non-return control component is used to prevent the air pressure on the side of the mass flow meter facing the first switching valve and the second switching valve from being greater than the air pressure on the side of the mass flow meter facing the air supply path.

9. The gas supply system according to claim 8, characterized in that: The non-return control component includes a vacuum gauge, which is used to measure the air pressure of the pipeline between the mass flow meter and the first switching valve or between the mass flow meter and the second switching valve.

10. The gas supply system according to claim 8, characterized in that: The non-return control component also includes a one-way valve, which is arranged between the air extraction pump and the mass flow meter; the one-way valve is configured to conduct only one-way from the mass flow meter to the air extraction pump.

11. The gas supply system according to claim 8, further comprising a controller, wherein the controller comprises: An acquisition module is used to obtain the breath-holding duration; a first control module, used for controlling a first switching valve to remain in a closed state and controlling a second switching valve to close, wherein the first switching valve is connected between a mass flow meter and a gas supply pipeline of a process chamber, and the second switching valve is connected between the mass flow meter and a vacuum pump; and The second control module is used to control the first switching valve to open after the breath holding time has passed. Open and close the second switching valve.

12. A semiconductor process equipment, characterized in that: A gas supply system comprising the gas supply system according to any one of claims 8 to 11.

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