Wafer transmission pressure control system and method

Abstract

The invention discloses a wafer transmission pressure control system and method, the system is applied to semiconductor process equipment, the system comprises a semiconductor process platform and process cavities, the semiconductor process platform comprises an equipment front-end module, a load locking cavity and a plurality of transmission cavities, the transmission cavities are used for sequentially transmitting wafers to each process cavity, and the equipment front-end module is connected with the load locking cavity. A control valve is arranged between the transmission cavity and the process cavity and used for controlling communication between the transmission cavity and the process cavity. Particle testing is carried out through the wafer transmission pressure control system, and the optimal pressure difference between the transmission cavity and the process cavity can be determined, so that the problem that by-products in the process cavity return to the transmission cavity through the transmission channel due to improper pressure and pressure difference between the transmission cavity and the process cavity can be solved; therefore, the use effect of the semiconductor process equipment is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor equipment, in particular to a wafer transfer pressure control system and method. BACKGROUND

[0002] In a semiconductor process equipment, such as a chemical vapor deposition (CVD) equipment, its structure generally comprises a platform and a process module (PM). The platform is further divided into an equipment front end module (EFEM), a load lock chamber (LL) and a transfer module (TM). The working process of the semiconductor process equipment is as follows: the wafer starts from the EFEM, enters the TM module through the LL module, and is transferred to different PM chambers through the vacuum robot set in the TM chamber for process treatment.

[0003] However, a large amount of by-products (such as particles) are generated in the PM chamber during the process. Since the TM chamber and the PM chamber are directly connected when the wafer is transferred, the by-products in the PM chamber are easy to enter the TM chamber through the wafer transfer channel when the gate valve between the two is opened, which causes the TM chamber to be contaminated. After long-term accumulation, the number of particles in the PM chamber will increase significantly, which directly affects the process performance and further causes the product yield to decrease.

[0004] In order to inhibit the by-products in the PM chamber from entering the TM chamber, the existing technology generally uses the method of controlling the pressure difference (ΔP) between the TM chamber and the PM chamber, and the pressure in the TM chamber is usually set to be greater than that in the PM chamber. The size of the pressure difference ΔP is generally adjusted by increasing the pressure in the TM chamber, but there is no mature method to determine its value at present, and it is mostly dependent on experience.

[0005] In practical application, the size of the pressure difference ΔP has a significant influence on the inhibition effect of the by-products: too small ΔP cannot completely prevent the by-products in the PM chamber from entering the TM chamber; and too large ΔP will cause too large air flow disturbance between the TM chamber and the PM chamber at the moment when the gate valve is opened, which also cannot effectively control the by-products in the PM chamber from entering the TM chamber. Therefore, in the scene of developing a new process or the hardware conditions of the TM chamber and the PM chamber changing (at this time, the past experience cannot guide the new equipment or new conditions), how to determine the optimal pressure difference between the TM chamber and the PM chamber is a problem to be solved by the person skilled in the art. SUMMARY

[0006] The embodiments of the present application provide a wafer transfer pressure control system and method, which aims to determine the optimal pressure difference between the transfer chamber and the process chamber in the semiconductor process equipment, and to improve the use effect of the semiconductor process equipment.

[0007] The embodiment of the present application provides a wafer transmission pressure control system, which is applied to a semiconductor process equipment, the semiconductor process equipment comprises a semiconductor process platform and process cavities, the semiconductor process platform comprises an equipment front end module, a load lock cavity and a transmission cavity, the process cavities are provided in plurality, the transmission cavity is used for sequentially transmitting wafers to each process cavity, a control valve is arranged between the transmission cavity and the process cavities, and the control valve is used for controlling the communication between the transmission cavity and the process cavities.

[0008] Further, the transmission cavity is connected with a transmission cavity pump, the transmission cavity is further provided with a pressure gauge, a mass flow meter and a throttle meter;

[0009] The pressure gauge is used for displaying the pressure value of the transmission cavity, the mass flow meter is used for controlling the gas flow rate flowing into the transmission cavity, and the throttle meter is used for adjusting the pumping speed of the transmission cavity pump.

[0010] Further, the process cavity is connected with a process cavity pump.

[0011] The embodiment of the present application further provides a wafer transmission pressure control method, which is applied to the wafer transmission pressure control system as any one of the above.

[0012] The semiconductor process equipment is subjected to cleaning treatment, and the semiconductor process equipment is subjected to particle testing to obtain a first particle testing result;

[0013] If the first particle testing result reaches a preset threshold value, the cleaning treatment and the particle testing are continuously performed until the first particle testing result reaches the preset threshold value;

[0014] If the first particle testing result does not reach the preset threshold value, the semiconductor process equipment is subjected to process flow processing, and the particle testing is performed after the process flow processing to obtain a second particle testing result;

[0015] A testing difference value between the first particle testing result and the second particle testing result is calculated;

[0016] When the testing difference value reaches a preset difference value, the transmission cavity pressure and the process cavity pressure of the transmission cavity and the process cavities are obtained, and a pressure difference value between the transmission cavity pressure and the process cavity pressure is taken as an optimal pressure difference;

[0017] The semiconductor process equipment is controlled to perform wafer transmission processing based on the optimal pressure difference.

[0018] Further, the particle testing on the semiconductor process equipment comprises:

[0019] The semiconductor process platform is tested by pre-prepared particles, and the purge operation is performed on each transfer cavity before the wafer is transferred to each process cavity in sequence.

[0020] Further, the purge operation on each transfer cavity includes:

[0021] The transfer cavity is supplied with a preset flow of gas to raise the pressure of the transfer cavity to a first preset pressure value;

[0022] The transfer cavity is pumped by the transfer cavity pump to reduce the pressure of the transfer cavity to a second preset pressure value;

[0023] The transfer cavity is particle extracted by the transfer cavity pump.

[0024] Further, the semiconductor process equipment is cleaned and particle tested to obtain the first particle test result before the step of:

[0025] The initial transfer cavity pressure and the initial process cavity pressure of the transfer cavity and the process cavity before the control valve is opened are obtained;

[0026] The initial pressure difference of the transfer cavity and the process cavity is calculated according to the initial transfer cavity pressure and the initial process cavity pressure.

[0027] Further, it also includes:

[0028] When the test difference does not reach the preset difference, the initial pressure difference is adjusted and the particle test is performed again until the optimal pressure difference is obtained.

[0029] Further, the adjustment of the initial pressure difference includes:

[0030] The pressure of the transfer cavity is adjusted by the mass flow meter and / or the throttle meter;

[0031] And / or, the pressure of the process cavity is adjusted by the process cavity pump.

[0032] Further, the cleaning of the semiconductor process equipment includes:

[0033] The semiconductor process platform is wet cleaned.

[0034] The embodiment of the present application provides a wafer transmission pressure control system and method, which is applied to a semiconductor process equipment, the semiconductor process equipment comprises a semiconductor process platform and process cavities, the semiconductor process platform comprises an equipment front end module, a load lock cavity and a transmission cavity, the process cavities are provided in plurality, the transmission cavity is used for transmitting wafers to each process cavity in sequence, a control valve is arranged between the transmission cavity and the process cavities, and the control valve is used for controlling the communication between the transmission cavity and the process cavities. The wafer transmission pressure control system is used for particle testing, and the optimal pressure difference of the transmission cavity and the process cavities in the semiconductor process equipment can be determined, so that the problems, such as that the by-products in the process cavities return to the transmission cavity through the transmission channel due to the unsuitable pressure and pressure difference of the transmission cavity and the process cavities, and then pollute the common path and even other process cavities, can be solved, and the use effect of the semiconductor process equipment is improved. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0036] Figure 1 A structural schematic diagram of a wafer transmission pressure control system provided by the embodiment of the present application is provided.

[0037] Figure 2 Another structural schematic diagram of a wafer transmission pressure control system provided by the embodiment of the present application is provided.

[0038] Figure 3 Still another structural schematic diagram of a wafer transmission pressure control system provided by the embodiment of the present application is provided.

[0039] Figure 4 A transmission cavity schematic diagram in a wafer transmission pressure control system provided by the embodiment of the present application is provided.

[0040] Figure 5 A process cavity schematic diagram in a wafer transmission pressure control system provided by the embodiment of the present application is provided.

[0041] Figure 6 A flow schematic diagram of a wafer transmission pressure control method provided by the embodiment of the present application is provided.

[0042] Identified in the figure:

[0043] 1, equipment front end module; 2, load lock chamber; 3, transfer chamber; 31, transfer chamber pump; 32, pressure gauge; 33, mass flow meter; 34, throttle meter; 35, transfer chamber robot; 4, process chamber; 41, process chamber pump; 5, control valve. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0045] It should be understood that, when used in the specification and the appended claims, the terms "comprise" and "include" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0046] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms, unless the context clearly indicates otherwise.

[0047] It should be further understood that the term "and / or" used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0048] Please see Figure 1 The embodiments of the present application provide a wafer transfer pressure control system, which is applied to a semiconductor process equipment, the semiconductor process equipment includes a semiconductor process platform and process chambers 4, the semiconductor process platform includes an equipment front end module 1, a load lock chamber 2 and a transfer chamber 3, the process chambers 4 are provided in plurality, the transfer chamber 3 is used for transferring wafers to each process chamber 4 in sequence, a control valve 5 is arranged between the transfer chamber 3 and the process chambers 4, and the control valve 5 is used for controlling the communication between the transfer chamber 3 and the process chambers 4.

[0049] The wafer transmission pressure control system is used for particle testing, so that the optimal pressure difference between the transmission cavity 3 and the process cavity 4 in the semiconductor process equipment can be determined, and thus the problems that the by-products in the process cavity 4 return to the transmission cavity 3 through the transmission channel due to the improper pressure and pressure difference ΔP between the transmission cavity 3 and the process cavity 4, and then pollute the common path and even other process cavities 4, etc. can be solved, so as to improve the use effect of the semiconductor process equipment.

[0050] The wafer Wafer is transmitted into the LL (load lock chamber 2) by the EFEM (equipment front end module 1), and then the wafer can be taken out from the LL by the TM Robot (transmission cavity robot 35), and after the SiltValve (SLV, that is, the control valve 5) between the TM cavity (transmission cavity 3) and the PM cavity (process cavity 4) is opened, the wafer is sent into the PM cavity. In this process, the pressure in the TM cavity before the SLV is opened is P T , the pressure in the PM cavity is P P , and the pressure difference ΔP between the TM cavity and the PM cavity is P T -P P . In this process, when the SLV is opened, if P T >P P , the gas in the TM cavity will enter the PM cavity through the SLV and the transmission channel between the TM cavity and the PM cavity, so as to inhibit the gas in the PM cavity from flowing into the TM cavity.

[0051] As shown in Figures 1 to 3 , the process cavity 4 is provided with three, that is, PM1, PM2 and PM3, and when the wafer is transmitted, the transmission cavity robot 35 will transmit the wafer to PM1, PM2 and PM3 in turn.

[0052] In a specific embodiment, as shown in Figure 4 , the transmission cavity 3 is connected with a transmission cavity pump 31, and the transmission cavity 3 is also provided with a pressure gauge 32, a mass flow meter 33 and a throttle meter 34.

[0053] The pressure gauge 32 is used for displaying the pressure value of the transmission cavity 3, the mass flow meter 33 is used for controlling the gas flow into the transmission cavity 3, and the throttle meter 34 is used for adjusting the pumping speed of the transmission cavity pump 31.

[0054] As can be seen from Figure 4 , the pressure gauge 32 is directly connected to the transmission cavity 3, the mass flow meter 33 is connected in parallel to the gas transmission channel of the transmission cavity 3, and the throttle meter 34 is arranged between the transmission cavity pump 31 and the transmission cavity 3. At the same time, a plurality of gate valves can also be combined to control the flow paths of the transmission cavity 3.

[0055] The pressure of the TM cavity is displayed by a Gauge (pressure gauge 32) connected to the TM cavity, and the TM cavity pressure is controlled in two ways, one is to control the flow of gas into the TM cavity by an MFC (mass flow controller 33) to adjust the TM cavity pressure, and the other is to adjust the TM cavity pressure by adjusting the pumping speed of the TM Pump through a TV (throttle valve 34). In actual application, for some devices without a TV between the TM Pump (transfer cavity pump 31) and the TM cavity, the pressure of the TM cavity can be controlled by controlling the flow of nitrogen N2 into the TM cavity. For example, when it is necessary to increase ΔP, the pressure of the TM cavity can be increased while keeping the pressure of the PM cavity unchanged, that is, by increasing the flow of the MFC or reducing the opening degree of the TV.

[0056] In another specific embodiment, in combination with Figure 5 , the process cavity 4 is connected with a process cavity pump 41. In actual application, the process cavity 4 can also be provided with a Gauge, an MFC, a gate valve and the like to control and adjust the pressure of the process cavity 4.

[0057] Another way to increase ΔP is to reduce the pressure of the PM cavity. Generally, the PM cavity has two control modes before wafer transfer, i.e. pressure control and no pressure control. When the PM cavity is in the no pressure control mode before wafer transfer, the PM cavity does not flow gas, and the TV valve connected with the PM Pump (process cavity pump 41) is fully open to pump the pressure of the PM cavity to the background pressure (i.e. the minimum pressure), which cannot be adjusted, and ΔP can only be increased by increasing the pressure of the TM cavity at this time. p At this time, ΔP can be increased by reducing P p . Similar to the TM cavity, reducing P p can be achieved by reducing the flow of the PM cavity or increasing the opening degree of the TV.

[0058] Figure 6 A flowchart of a wafer transfer pressure control method provided by an embodiment of the present application is shown, which is applied to the wafer transfer pressure control system as described above, and the method specifically includes steps S101-S106.

[0059] In step S101, the semiconductor process equipment is cleaned and particle testing is performed on the semiconductor process equipment to obtain a first particle testing result.

[0060] In step S102, if the first particle testing result reaches a preset threshold, the cleaning and particle testing are continued until the first particle testing result reaches the preset threshold.

[0061] Step S103, if the first particle test result does not reach the preset threshold, the semiconductor process equipment is processed by process flow processing, and particle test is performed after the process flow processing to obtain a second particle test result;

[0062] Step S104, a test difference between the first particle test result and the second particle test result is calculated;

[0063] Step S105, when the test difference reaches a preset difference value, the transmission cavity pressure and the process cavity pressure of the transmission cavity 3 and the process cavity 4 are obtained, and a pressure difference between the transmission cavity pressure and the process cavity pressure is taken as an optimal pressure difference;

[0064] Step S106, the semiconductor process equipment is controlled based on the optimal pressure difference to perform wafer transmission processing.

[0065] In order to determine the optimal pressure difference between the transmission cavity 3 and the process cavity 4, the wafer transmission pressure control system is based on, first, the semiconductor process equipment is cleaned and particle tested to obtain an initial first particle test result. If the initial first particle test result does not reach the preset threshold, the cleaning and particle testing are performed again until the requirement is met. Then, the process flow processing is performed, and the wafer after processing is particle tested to obtain a second particle test result. By comparing the test difference between the first particle test result and the second particle test result, the influence of the process flow processing on the wafer cleanliness can be evaluated. When the test difference reaches the preset difference value, it means that the influence of the process flow processing on the wafer cleanliness is within an acceptable range, at which time the optimal pressure difference between the transmission cavity 3 and the process cavity 4 can be further determined. Further, the semiconductor process equipment can be processed according to the obtained optimal pressure difference for wafer transmission processing to ensure that the wafer is not contaminated in the transmission process.

[0066] In an embodiment, the particle test on the semiconductor process equipment includes:

[0067] The semiconductor process platform is tested by a pre-planned particle transmission cycle, and a Purge operation is performed on each transmission cavity 3 before the wafer is sequentially transmitted to each process cavity 4 by the transmission cavity 3.

[0068] Specifically, the Purge operation on each transmission cavity 3 includes:

[0069] A gas with a preset flow rate is introduced into the transmission cavity 3 to raise the pressure of the transmission cavity 3 to a first preset pressure value;

[0070] The transmission cavity 3 is pumped by the transmission cavity pump 31 to reduce the pressure of the transmission cavity 3 to a second preset pressure value;

[0071] The transfer chamber 3 is used to extract particles through the transfer chamber pump 31.

[0072] In this embodiment, when performing particle testing, the particle performance of the platform under different conditions can be tested, and the particle size to be tested can be determined as needed, such as 0.026μm, 0.037μm, or even smaller, such as 0.019μm.

[0073] During testing, the PA performance (EFEM-LL-TM) was first tested after a specified number of cycles on the normal Cycle platform, and the number of PAs was recorded as A1. Next, the performance was tested when the TM Robot was facing PM1, PM2, and PM3 respectively. Figures 1 to 3 As shown, after performing a specified number of purging operations on the TM cavity, the PA counts were recorded as B1, C1, and D1. A purging operation involves injecting a large amount of gas into the TM cavity to raise the TM pressure to a higher value, and then pumping the pressure down to a lower value. The purpose is to lift the particles within the TM cavity and remove them using a pump, thus cleaning the TM cavity. During the test, the number of cycles or purgings can be set according to actual needs. Generally, the PA count on the test platform is specified as a certain number of cycles, such as 5-10 cycles, requiring the number of particles larger than a certain size to be less than a specified value. For example, 10Cycle@0.026<10 means that within 10 cycles, the number of particles larger than 0.026 micrometers is less than 10. A cycle, depending on the path, generally refers to the wafer being removed from the EFEM FOUP (wafer transfer cassette), entering the lower LL layer via the EFEM Robot, then being removed by the TM Robot, and finally being transported to the upper LL layer by the EFEM Robot. This constitutes one cycle. A 10-cycle cycle means the EFEM Robot transports the wafer back to the lower LL layer, and this cycle is repeated 10 times. The EFEM-LL-TM mentioned above refers to the corresponding cycle path. A purge operation involves closing the TM evacuation, backfilling the TM cavity from a low pressure to a higher pressure, then closing the backfill and evacuating it from the higher pressure to a lower pressure. For example, if the lower pressure of the TM cavity is 0.1 Torr and the higher pressure is 200 Torr, a purge operation can backfill the TM cavity to 200 Torr and then evacuate it to 0.1 Torr. This cycle from 0.1 to 200 and back to 0.1 constitutes one cycle. A specified number of purge operations on the TM cavity refers to executing the corresponding number of cycles according to a predetermined number of times.

[0074] In an embodiment, before the step of cleaning the semiconductor process equipment and performing a particle test on the semiconductor process equipment to obtain a first particle test result, the method comprises:

[0075] obtaining an initial transfer chamber pressure and an initial process chamber pressure of the transfer chamber 3 and the process chamber 4 before the control valve 5 is opened;

[0076] calculating an initial pressure difference between the transfer chamber 3 and the process chamber 4 based on the initial transfer chamber pressure and the initial process chamber pressure.

[0077] In this embodiment, before performing the particle test, the initial transfer chamber pressure and the initial process chamber pressure of the transfer chamber 3 and the process chamber 4 before the SLV control valve 5 is opened are obtained, and the initial pressure difference between the transfer chamber 3 and the process chamber 4 is calculated based on the two initial pressure values. The purpose of this step is to understand the pressure state between the transfer chamber 3 and the process chamber 4 before wafer transfer starts, so as to provide basic data for subsequent pressure control and determination of the optimal pressure difference. By accurately measuring and calculating the initial pressure difference, the pressure conditions during wafer transfer can be more effectively adjusted and controlled, thereby further reducing the risk of wafer contamination and improving the overall performance of the semiconductor process equipment and the production quality of the wafer.

[0078] Further, in an embodiment, the wafer transfer pressure control method further comprises:

[0079] When the test difference does not reach the preset difference, the initial pressure difference is adjusted, and the particle test is performed again until the optimal pressure difference is obtained.

[0080] In this embodiment, when the test difference is lower than the preset difference, pressure adjustment is performed based on the obtained initial pressure difference, and the particle test is performed again after the adjustment to evaluate the impact of pressure adjustment on wafer cleanliness. This iterative process continues until the test difference reaches the preset difference, at which point the optimal pressure difference is considered to have been found, which can minimize the risk of wafer contamination during the transfer process.

[0081] Specifically, the adjustment of the initial pressure difference comprises:

[0082] adjusting the pressure of the transfer chamber 3 by the mass flow meter 33 and / or the throttle meter 34;

[0083] and / or, adjusting the pressure of the process chamber 4 by the process chamber pump 41.

[0084] When adjusting the pressure difference between the transfer chamber 3 and the process chamber 4, on one hand, the gas flow into the transfer chamber 3 can be precisely controlled by the mass flow meter 33, so as to finely adjust the pressure of the transfer chamber. On the other hand, the pumping speed of the transfer chamber pump 31 can be adjusted by the throttle meter 34, so as to further precisely control the pressure of the transfer chamber 3. Meanwhile, the pressure of the process chamber 4 can also be adjusted by the process chamber pump 41, so as to ensure that the pressure of the process chamber 4 is stably within a given range.

[0085] For example, when it is required to increase the pressure difference, the pressure of the transfer chamber 3 can be reduced by reducing the gas flow of the mass flow meter 33 or increasing the pumping speed of the throttle meter 34. Meanwhile, the pressure of the process chamber 4 can also be adjusted by the process chamber pump 41, so as to achieve the required pressure difference. Such a multi-mode pressure adjustment mechanism enables the embodiment to more flexibly and precisely control the pressure difference between the transfer chamber 3 and the process chamber 4, so as to meet the cleanliness requirement of the semiconductor process equipment in the wafer transfer process.

[0086] In specific embodiments, the cleaning process for the semiconductor process equipment includes:

[0087] The semiconductor process platform is subjected to a wet cleaning process.

[0088] The embodiment adopts a wet cleaning method to clean the semiconductor process platform. The wet cleaning process can effectively remove impurities and particles on the wafer and the surface of the equipment, so as to ensure the cleanliness of the wafer in the transfer and processing process. The wet cleaning process can use pure water or alcohol solution or other appropriate cleaning agents to enhance the cleaning effect. After the cleaning is completed, the semiconductor process equipment is subjected to a particle test again, so as to verify the cleaning effect and ensure that the cleanliness of the wafer transfer environment meets the process requirement.

[0089] In actual application, when performing the particle test, first, the PA performance of the normal Cycle platform after a specified number of times is tested (EFEM-LL-TM), and the number of PAs is recorded as A1; second, the PAs are removed from the TM chamber by the Purge operation when the TM Robot is directed to PM1, PM2 and PM3, respectively, and the number of PAs is recorded as B1, C1 and D1 (A1, B1, C1 and D1 are the first particle test results) after a specified number of times of Purge operation. During the test, the number of times of Cycle or Purge can be set according to actual requirement. Figure 4 , Figure 5 and Figure 6

[0090] ​Further, it is compared whether A1 is less than a preset SPEC value N1, and whether the values of B1, C1 and D1 are less than a preset SPEC value N2. Wherein, N1 < N2, for example, N1 = 30, N2 = 100. Here, the SPEC values N1 and N2 refer to the maximum number of particles greater than a certain size under different operation modes, for example, N1 = 30, N2 = 100, which means that the maximum number of particles greater than 0.026 microns should be less than 30 and 100 during the test.

[0091] When A1, B1, C1 and D1 all meet the SPEC requirements, i.e. A1 < N1, B1, C1 and D1 are all < N2, then the next process Run wafer test is performed. Wherein, the process Run wafer can exceed N3 times, N3 = 200, of course, N3 can also be other specified values. Otherwise, the Wet Clean should be continued on the platform until the SPEC is met, and the next step can be performed.

[0092] After the process Run wafer is completed, the above test is repeated again, and the corresponding PA data (i.e. the second particle test result) A2, B2, C2 and D2 are collected; then the difference values ΔA = A2-A1, ΔB = B2-B1, ΔC = C2-C1 and ΔD = D2-D1 < M2 are calculated, and these difference values are compared with the preset SPEC values M1 and M2. Wherein, M1 < M2, for example, M1 = 5, M2 = 20. Here, M1 and M2 refer to the change value of the particle number between A1 and A2, B1 and B2, C1 and C2, and D1 and D2 measured before and after the process in the PM chamber, for example, if M1 is 5, it means that the difference between the particle number measured after the process in the PM chamber and the particle number measured before the process should not be greater than 5. It should be noted that N1 and N2 reflect the cleanliness of the TM chamber environment, and the measured particle number less than N1 and N2 can be considered as clean TM chamber, while M1 and M2 are the change degree of cleanliness, for example, when the change value is less than M1 and M2, it can be considered that the chamber still maintains a clean state with little change after the process, otherwise, if the measured particle number is greater than M1 and M2, it is considered that the chamber cleanliness has changed greatly.

[0093] If ΔA < Ml, ΔB < M2, ΔC < M2, and ΔD < M2 are true, it indicates that the pressures and pressure differentials of the TM chamber and the PM chamber are at the optimal pressure differentials under the conditions of the processes being tested in the flowchart. If ΔA < Ml, ΔB < M2, ΔC < M2, and ΔD < M2 are not true, the initial pressure differential should be increased and the PA test should be performed again until ΔA < Ml, ΔB < M2, ΔC < M2, and ΔD < M2 are true. Here, if A2, B2, C2, and D2 obtained previously still satisfy A2 < Nl, B2, C2, and D2 are all less than N2, the particle test can be performed directly, otherwise, the semiconductor process platform should be cleaned wetly before the particle test is performed.

[0094] It should also be noted that when the production conditions change, such as the pressure of the transfer chamber 3 TM or the process chamber 4 PM changes, the process changes, the hardware of the semiconductor process platform or the process chamber 4 PM changes, etc., even if the pressure differential ΔP between the transfer chamber 3 and the pressure chamber remains unchanged, the test should still be performed again. In addition, when multiple process chambers 4 perform different processes respectively, each process needs to be tested to ensure that the pressure and pressure differential of the platform can adapt to the process conditions of all process chambers 4.

[0095] The various embodiments described in the specification are progressive in nature, and each embodiment focuses on the differences from other embodiments. The same or similar parts between various embodiments can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant part can be referred to the method part. It should be noted that for those skilled in the art, without departing from the principles of the present application, some improvements and modifications can be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

[0096] It should also be noted that in the specification, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or equipment including the element.

Claims

1. A wafer transfer pressure control system applied to a semiconductor process equipment, the semiconductor process equipment comprising a semiconductor process platform and a process chamber, the semiconductor process platform comprising an equipment front end module, a load lock chamber and a transfer chamber, characterized in that, The process cavity is provided with a plurality of transmission cavities, the transmission cavities are used for transmitting wafers to each process cavity in sequence, and control valves are arranged between the transmission cavities and the process cavities, and the control valves are used for controlling the communication between the transmission cavities and the process cavities.

2. The wafer transfer pressure control method according to claim 1, wherein The transmission cavities are connected with transmission cavity pumps, and the transmission cavities are further provided with pressure gauges, mass flow meters and throttling meters. The pressure gauges are used for displaying the pressure values of the transmission cavities, the mass flow meters are used for controlling the gas flow rates flowing into the transmission cavities, and the throttling meters are used for adjusting the pumping speeds of the transmission cavity pumps.

3. The wafer transfer pressure control method of claim 1, wherein The process cavities are connected with process cavity pumps.

4. A wafer transfer pressure control method applied to the wafer transfer pressure control system according to any one of claims 1 to 3, characterized by, The method comprises the following steps: cleaning a semiconductor process equipment and performing a particle test on the semiconductor process equipment to obtain a first particle test result; if the first particle test result reaches a preset threshold value, the cleaning and the particle test are continuously performed until the first particle test result reaches the preset threshold value; if the first particle test result does not reach the preset threshold value, a process flow processing is performed on the semiconductor process equipment, and a particle test is performed after the process flow processing to obtain a second particle test result; a test difference value between the first particle test result and the second particle test result is calculated; when the test difference value reaches a preset difference value, a transmission cavity pressure of the transmission cavities and a process cavity pressure of the process cavities are obtained, and a pressure difference value between the transmission cavity pressure and the process cavity pressure is taken as an optimal pressure difference; the semiconductor process equipment is controlled based on the optimal pressure difference to perform a wafer transmission processing.

5. The wafer transfer pressure control method according to claim 4, wherein The particle test on the semiconductor process equipment comprises the following steps: a transmission cycle test is performed on the semiconductor process platform by using pre-planned particles, and a Purge operation is performed on each transmission cavity before the transmission cavities control the wafers to be transmitted to each process cavity in sequence.

6. The wafer transfer pressure control method according to claim 5, applied to the wafer transfer pressure control system according to claim 2, wherein The Purge operation performed on each transmission cavity comprises the following steps: a preset flow rate of gas is introduced into the transmission cavity, so that the pressure of the transmission cavity is increased to a first preset pressure value; the transmission cavity is subjected to a gas extraction processing by the transmission cavity pump, so that the pressure of the transmission cavity is decreased to a second preset pressure value; the transmission cavity is subjected to a particle extraction processing by the transmission cavity pump.

7. The wafer transfer pressure control method of claim 4, wherein, Before the step of cleaning the semiconductor process equipment and performing a particle test on the semiconductor process equipment to obtain a first particle test result, the following steps are further included: initial transmission cavity pressures and initial process cavity pressures of the transmission cavities and the process cavities before the control valves are opened are obtained; an initial pressure difference of the transmission cavities and the process cavities is calculated according to the initial transmission cavity pressures and the initial process cavity pressures.

8. The wafer transfer pressure control method according to claim 7, wherein Further comprising the following steps: when the test difference value does not reach the preset difference value, the initial pressure difference is adjusted, and the particle test is re-performed until the optimal pressure difference is obtained.

9. The wafer transfer pressure control method according to claim 8, applied to the wafer transfer pressure control system according to claim 2 or 3, wherein The adjustment of the initial pressure difference comprises the following steps: the pressure of the transmission cavity is adjusted by the mass flow meter and / or the throttling meter; and / or, the pressure of the process cavity is adjusted by the process cavity pump.

10. The wafer transfer pressure control method of claim 4, wherein, The cleaning of the semiconductor process equipment comprises the following steps: a wet cleaning processing is performed on the semiconductor process platform.

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