Vacuum degree threshold determination method and device, equipment, medium and product

Abstract

The invention discloses a method, a device and equipment for determining a vacuum degree threshold value, a medium and a product, and relates to the technical field of electron beam measurement, and the method for determining the vacuum degree threshold value comprises the steps: carrying out the vacuum pumping operation of a transmission cavity after the transmission cavity of a charged particle beam imaging device transmits a target wafer; the vacuum degrees of the transmission cavity at multiple moments in the vacuumizing operation execution process are obtained; a target first vacuum degree curve matched with the vacuum degrees at the multiple moments is searched from all first vacuum degree curves in a database, and the database comprises the multiple first vacuum degree curves and corresponding vacuum degree stable values; each first vacuum degree curve is used for representing the change trend of the vacuum degree of the transmission cavity after the wafers with different deflation amounts are transmitted into the transmission cavity; and determining a vacuum degree stable value corresponding to the target first vacuum degree curve as a target vacuum degree threshold value of the transmission cavity corresponding to the target wafer.

Description

Technical Field

[0001] The present application belongs to the field of electron beam measurement technology, and in particular, relates to a method, device, equipment, medium and product for determining a vacuum threshold. Background Art

[0002] In current electron beam measurement equipment, the transfer chamber serves as a transition between the atmosphere and the vacuum state. Before performing electron beam measurement on a wafer, the wafer needs to be evacuated to a preset vacuum threshold in the transfer chamber, and then the transfer valve is opened to transfer the wafer to the main vacuum chamber to avoid large vacuum fluctuations in the main vacuum chamber.

[0003] In the existing method, the machine is first switched to the corresponding mode and then the transfer chamber is evacuated. After the vacuum reaches the preset vacuum threshold of the mode, the vacuum valve of the transfer chamber is closed to stop evacuating the transfer chamber. If the vacuum of the transfer chamber is not less than the preset vacuum threshold after waiting for a period of time, the wafer is transferred to the main chamber.

[0004] However, if the vacuum level of the transfer chamber is less than the preset vacuum level threshold after a period of time, it means that the wafer itself is still outgassing, and the preset vacuum level threshold is not accurate enough, so the transfer chamber needs to be evacuated further. In this way, the accuracy of the vacuum level threshold setting of the transfer chamber is not high, which will greatly extend the evacuation time, resulting in a low measurement throughput of the transfer chamber. Summary of the invention

[0005] The embodiments of the present application provide a method, device, equipment, medium and product for determining a vacuum threshold, which can improve the measurement throughput of a transmission cavity.

[0006] In one aspect of an embodiment of the present application, a method for determining a vacuum threshold is provided, comprising:

[0007] After the target wafer is transferred into the transmission cavity of the charged particle beam imaging device, a vacuum operation is performed on the transmission cavity;

[0008] Acquiring the vacuum degree of the transmission chamber at multiple moments during the process of performing the vacuum pumping operation;

[0009] Searching for a target first vacuum degree curve that matches the vacuum degree at multiple moments from each first vacuum degree curve in the database, wherein the database includes multiple first vacuum degree curves and corresponding vacuum degree stability values, and each first vacuum degree curve is used to characterize a change trend of the vacuum degree of the transfer chamber after wafers with different degassing amounts are introduced;

[0010] The vacuum degree stability value corresponding to the target first vacuum degree curve is determined as the target vacuum degree threshold value of the transmission cavity corresponding to the target wafer.

[0011] In one aspect of an embodiment of the present application, a device for determining a vacuum degree threshold is provided, comprising:

[0012] A transmission cavity vacuuming module, used to perform a vacuuming operation on the transmission cavity after the target wafer is transferred into the transmission cavity of the charged particle beam imaging device;

[0013] A vacuum degree acquisition module, used to acquire the vacuum degree of the transmission chamber at multiple moments during the vacuum pumping operation;

[0014] A curve matching module, used to search for a target first vacuum degree curve that matches the vacuum degree at multiple moments from each first vacuum degree curve in the database, wherein the database includes multiple first vacuum degree curves and corresponding vacuum degree stability values, and each first vacuum degree curve is used to characterize a change trend of the vacuum degree of the transfer chamber after wafers with different degassing amounts are introduced;

[0015] The threshold determination module is used to determine the vacuum degree stability value corresponding to the target first vacuum degree curve as the target vacuum degree threshold of the transmission cavity corresponding to the target wafer.

[0016] According to one aspect of an embodiment of the present application, an electronic device is provided, which includes: a memory and a program or instruction stored in the memory and executable on a processor, wherein when the program or instruction is executed by the processor, a method for determining a vacuum degree threshold value as provided in any aspect of the above-mentioned embodiment of the present application is implemented.

[0017] According to one aspect of an embodiment of the present application, a readable storage medium is provided, on which a program or instruction is stored. When the program or instruction is executed by a processor, a method for determining a vacuum degree threshold value provided in any aspect of the above-mentioned embodiment of the present application is implemented.

[0018] According to one aspect of an embodiment of the present application, a computer program product is provided. When instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes a method for determining a vacuum degree threshold value as provided in any aspect of the above-mentioned embodiment of the present application.

[0019] In the method for determining the vacuum degree threshold provided in the embodiment of the present application, a database is pre-set, and the first vacuum degree curve corresponding to the transmission cavity after the wafers with different degassing amounts are transmitted and the vacuum degree stability value corresponding to the first vacuum degree curve are stored in the database. Then, the vacuum degree of the transmission cavity where the target wafer is located at multiple moments during the process of performing the vacuum pumping operation is compared with each first vacuum degree curve in the database to obtain the target first vacuum degree curve corresponding to the target wafer. Thereby, the type of degassing amount corresponding to the target wafer can be determined, and the vacuum degree threshold of the transmission cavity where the target wafer is located can be accurately obtained. In this way, the embodiment of the present application accurately determines the vacuum degree threshold of the transmission cavity where the target wafer is located by matching the target first vacuum degree curve with the target wafer. Avoiding the problem of a significant extension of the vacuum pumping time due to inaccurate setting of the vacuum degree threshold can improve the measurement throughput of the transmission cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 It is a flowchart of a method for determining a vacuum degree threshold provided by an embodiment of the present application;

[0022] Figure 2 It is a schematic diagram of a standard gas pressure curve of a transmission chamber where a target wafer is located provided by an embodiment of the present application;

[0023] Figure 3 It is a structural schematic diagram of a device for determining a vacuum degree threshold value provided by an embodiment of the present application;

[0024] Figure 4 It is a structural schematic diagram of a device for determining a vacuum degree threshold provided in one embodiment of the present application. DETAILED DESCRIPTION

[0025] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0026] It should be noted that, in this article, relational terms such as first and second, etc. 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 these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0027] It should be noted that the acquisition, storage, use, and processing of data in the technical solution of this application are in compliance with the relevant provisions of national laws and regulations.

[0028] It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, and they should be regarded as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0029] In the existing method, the machine is first switched to the corresponding mode and then the transfer chamber is evacuated. After the evacuation reaches the preset vacuum threshold of the mode, the evacuation valve of the transfer chamber is closed to stop evacuating the transfer chamber. If the vacuum of the transfer chamber is not less than the preset vacuum threshold after waiting for a period of time, the wafer is transferred to the main chamber. However, the accuracy of the vacuum threshold setting of the transfer chamber in this method is not high, which will cause the evacuation time to be greatly extended, resulting in a low measurement throughput of the transfer chamber.

[0030] The purpose of the present application is to provide a method, device, equipment, medium and product for determining a vacuum threshold. In the method for determining a vacuum threshold provided in the embodiment of the present application, a database is pre-set, and the first vacuum curve corresponding to the transmission cavity after the wafers with different degassing amounts are transferred into the database and the vacuum stability value corresponding to the first vacuum curve is stored in the database. Then, the vacuum degree of the transmission cavity where the target wafer is located at multiple moments during the process of performing the vacuum pumping operation is compared with each first vacuum curve in the database to obtain the target first vacuum curve corresponding to the target wafer. Thereby, the type of degassing amount corresponding to the target wafer can be determined, and the vacuum threshold of the transmission cavity where the target wafer is located can be accurately obtained. In this way, the embodiment of the present application accurately determines the vacuum threshold of the transmission cavity where the target wafer is located by matching the target first vacuum curve with the target wafer. Avoiding the problem of a significant extension of the vacuum pumping time caused by inaccurate setting of the vacuum threshold can improve the measurement throughput of the transmission cavity.

[0031] The following describes specific embodiments of the method, device, equipment, medium and product for determining the vacuum threshold provided by the embodiments of the present application. First, the method for determining the vacuum threshold is described.

[0032] Figure 1 A flow chart of a method for determining a vacuum degree threshold is provided. The method for determining a vacuum degree threshold can be applied to a server. The method for determining a vacuum degree threshold can include the following steps S101 to S104.

[0033] S101, after the target wafer is transferred into the transmission cavity of the charged particle beam imaging device, a vacuum operation is performed on the transmission cavity.

[0034] In this embodiment, the vacuum operation refers to the process of removing air, non-condensable gas and moisture in the transfer chamber by using a vacuum pump or other equipment to achieve a relatively vacuum state. It is used to adjust the vacuum degree in the transfer chamber to achieve the wafer transfer condition for transferring the target wafer in the transfer chamber to the main vacuum chamber.

[0035] S102, obtaining the vacuum degree of the transmission chamber at multiple moments during the process of performing the vacuum pumping operation.

[0036] In this embodiment, during the process of performing the vacuum pumping operation in the transmission chamber, the vacuum degree in the transmission chamber will change in real time, that is, during the process of performing the vacuum pumping operation, the vacuum degree of the transmission chamber at each moment is different.

[0037] As an example, the server sets a sensor in the transmission chamber, which can measure and record vacuum data in real time. When the target wafer enters the transmission chamber, the sensor is started to record the vacuum data of the transmission chamber at multiple times (for example, every 1 second, 5 seconds, or a time interval set according to actual needs).

[0038] The sensor may be a capacitive, piezoresistive or thermal conductivity vacuum gauge, and the vacuum degree data includes a timestamp and a corresponding vacuum degree value.

[0039] S103, searching for a target first vacuum degree curve that matches the vacuum degree at multiple moments from each first vacuum degree curve in the database, wherein the database includes multiple first vacuum degree curves and corresponding vacuum degree stability values, and each first vacuum degree curve is used to characterize a change trend of the vacuum degree of the transfer chamber after wafers with different degassing amounts are transferred into the transfer chamber.

[0040] In this embodiment, a plurality of first vacuum degree curves are pre-stored in the database, each of which corresponds to a specific wafer degassing amount and represents a change trend of the vacuum degree of the transfer chamber after a wafer with a corresponding degassing amount is transferred into the transfer chamber.

[0041] As an example, the server compares the recorded vacuum degree data with the first vacuum degree curve in the database to find the target first vacuum degree curve that best matches the current vacuum degree data.

[0042] The matching process can be implemented using algorithms such as least squares method, dynamic time warping (DTW) or machine learning models.

[0043] S104, determining a vacuum degree stability value corresponding to the target first vacuum degree curve as a target vacuum degree threshold value of the transfer cavity corresponding to the target wafer.

[0044] In this embodiment, the vacuum degree stability value is the vacuum degree value corresponding to when the vacuum degree in the target first vacuum degree curve tends to be stable.

[0045] As an example, after finding the target first vacuum degree curve, the server obtains a vacuum degree stability value from the target first vacuum degree curve, and determines the vacuum degree stability value corresponding to the target first vacuum degree curve as the target vacuum degree threshold corresponding to the target wafer.

[0046] Then, the service end continuously monitors the vacuum level in the transfer chamber. When the vacuum level is better than or equal to the target vacuum level threshold, the transfer mechanism is triggered to safely transfer the target wafer from the transfer chamber to the main vacuum chamber for the next step of processing.

[0047] Among them, a better vacuum degree means a lower air pressure in the transmission chamber. The transmission mechanism can be a robot arm, a conveyor belt or any other automated equipment, and the specific selection can depend on the layout of the production line and the size of the wafer. In the method for determining the vacuum threshold provided in this embodiment, a database is pre-set, and the database stores the first vacuum curve corresponding to the transmission chamber after the wafers with different degassing amounts are transferred and the vacuum stability value corresponding to the first vacuum curve. Then, the vacuum degree of the transmission chamber where the target wafer is located at multiple moments during the process of performing the vacuum pumping operation is compared with each first vacuum curve in the database to obtain the target first vacuum curve corresponding to the target wafer. Thereby, the type of degassing amount corresponding to the target wafer can be determined, and the vacuum threshold of the transmission chamber where the target wafer is located can be accurately obtained. In this way, the embodiment of the present application accurately determines the vacuum threshold of the transmission chamber where the target wafer is located by matching the target first vacuum curve with the target wafer. Avoiding the problem of a significant extension of the vacuum pumping time caused by inaccurate setting of the vacuum threshold can improve the measurement throughput of the transmission chamber.

[0048] As an optional embodiment, after S102, the method for determining the vacuum degree threshold may further include:

[0049] Obtaining the fluctuation duration of the vacuum degree from the start to the point where it reaches stability in the target first vacuum degree curve;

[0050] When the difference between the fluctuation duration and the current actual vacuuming duration corresponding to the vacuuming operation performed in the transmission chamber is greater than the preset interval duration, the vacuum degree of the transmission chamber at multiple moments in the preset time period is periodically obtained until the preset condition is met, thereby obtaining a target second vacuum degree curve;

[0051] The preset condition is that the difference between the current actual vacuuming time of the transmission chamber and the fluctuation time of the second vacuum degree curve is less than or equal to the preset interval time, and the second vacuum degree curve is a first vacuum degree curve in the database that matches the vacuum degrees at multiple moments after the vacuum degrees are periodically obtained;

[0052] S104 may specifically include:

[0053] The vacuum stability value corresponding to the target second vacuum curve is determined as the target vacuum threshold of the transfer chamber corresponding to the target wafer. In this embodiment, the fluctuation duration refers to the time period from when the vacuum fluctuates from the initial value to when it reaches a stable state, that is, the predicted vacuum pumping duration corresponding to the vacuum curve.

[0054] The current actual vacuuming duration is used to characterize the duration of the transmission chamber from the start of the vacuuming operation to the current moment. For example, the current actual vacuuming duration can be 5 seconds, 10 seconds or 15 seconds. As an example, the server obtains the target first vacuum degree curve, and then obtains the fluctuation duration T1 corresponding to the target first vacuum degree curve based on the moment corresponding to the first vacuum degree in the target first vacuum degree curve and the moment corresponding to the first vacuum degree that reaches a stable state.

[0055] Then, the current actual vacuuming time T2 of the transmission chamber is obtained, and the fluctuation time T1 is subtracted from the current actual vacuuming time T2 to obtain ΔT. If ΔT is greater than a preset interval (e.g., 10 seconds), the vacuum degree data of the transmission chamber at multiple moments within a preset period (e.g., every 5 seconds) is periodically obtained.

[0056] Then, all the acquired vacuum degree data are matched with the first vacuum degree curves preset in the database, and the first vacuum degree curve matching the vacuum degree at multiple moments within the current actual vacuuming duration is found to obtain the second vacuum degree curve.

[0057] Repeat the above steps until the difference between the current actual vacuum pumping time (T2') of the transfer chamber and the fluctuation time (T1') of the second vacuum curve is less than or equal to the preset interval time, and then determine the final corresponding second vacuum curve as the target second vacuum curve, and determine the vacuum stability value corresponding to the target second vacuum curve as the target vacuum threshold corresponding to the target wafer.

[0058] Through this embodiment, the vacuum degree of the transmission chamber at multiple moments within a preset period is periodically obtained, and then cyclically matched with each first vacuum degree curve in the database until the predicted vacuum pumping end time is approaching. By obtaining the vacuum degree of the transmission chamber as much as possible, the matching accuracy can be improved, and the vacuum degree threshold of the transmission chamber where the target wafer is located can be accurately determined.

[0059] As an optional embodiment, before periodically acquiring the vacuum degree of the transmission chamber at multiple moments within a preset time period, the method for determining the vacuum degree threshold may further include:

[0060] The duration of the preset period is determined according to the difference between the fluctuation duration and the current actual vacuuming duration, and the duration of the preset period is less than the difference.

[0061] In this embodiment, assuming that the fluctuation duration is 20 seconds and the current actual vacuuming duration is 5 seconds, the difference between the fluctuation duration and the current actual vacuuming duration is 15 seconds, that is, there are still 15 seconds left to predict the end of vacuuming.

[0062] At this time, the preset time period needs to be less than 15 seconds, so as to avoid excessive vacuuming due to exceeding 15 seconds, thereby prolonging the vacuuming time and causing a lower measurement throughput of the transmission chamber.

[0063] Furthermore, the preset time period can be as close as possible to the difference between the fluctuation duration and the current actual vacuuming duration. For example, assuming that the difference between the fluctuation duration and the current actual vacuuming duration is 15 seconds, the preset interval duration is 5 seconds, that is, the vacuum threshold of the transfer chamber where the target wafer is located should be determined 5 seconds before the predicted end of vacuuming.

[0064] Therefore, the preset period can be directly set to 15-5=10 seconds. At this time, only one periodic vacuum acquisition is required, that is, only one matching verification with the first vacuum curve in the database is required, which can reduce the repetitiveness of calculation and the consumption of computing resources.

[0065] Through this embodiment, the duration of the preset period is determined according to the difference between the fluctuation duration and the current actual vacuum pumping duration, which is helpful for the subsequent periodic acquisition of the vacuum degree according to the preset period. By acquiring the vacuum degree of the transmission cavity as much as possible, the matching accuracy can be improved, and the vacuum degree threshold of the transmission cavity where the target wafer is located can be accurately determined.

[0066] As an optional embodiment, S103 may specifically include:

[0067] Fitting the vacuum degrees at multiple moments to obtain a third vacuum degree curve of the transmission cavity;

[0068] A target first vacuum degree curve matching the third vacuum degree curve is searched from each first vacuum degree curve in the database.

[0069] In this embodiment, the third vacuum degree curve is a curve of the change trend of the vacuum degree of the target wafer in the transfer chamber obtained by fitting the vacuum degrees at multiple moments.

[0070] As an example, during the process of evacuating or maintaining the vacuum state of the transmission chamber, the server uses a high-precision vacuum sensor to obtain vacuum data at multiple moments in real time.

[0071] Then, the vacuum degree data acquired at multiple moments are input into a fitting algorithm, such as polynomial fitting, exponential fitting or neural network fitting, so as to obtain a third vacuum degree curve by fitting. The third vacuum degree curve can accurately reflect the change pattern of the vacuum degree in the transmission cavity where the target wafer is located over time.

[0072] Then, a suitable matching algorithm is used to match the third vacuum degree curve with each first vacuum degree curve in the database. The matching algorithm can compare based on characteristic parameters such as the shape, slope, maximum value, and minimum value of the curve.

[0073] Finally, according to the matching degree (such as similarity, error, etc.), the first vacuum degree curve that best matches the third vacuum degree curve is selected as the target first vacuum degree curve.

[0074] Through this embodiment, the vacuum degree data at multiple moments are fitted to obtain a third vacuum degree curve, and a target first vacuum degree curve matching the third vacuum degree curve is searched from a database. Thus, the target vacuum degree threshold corresponding to the target wafer can be accurately determined according to the target first vacuum degree curve in the database.

[0075] As an optional embodiment, after searching the first vacuum degree curves in the database for a target first vacuum degree curve that matches the vacuum degrees at multiple moments, the method for determining the vacuum degree threshold may further include:

[0076] When there is no target first vacuum degree curve matching the third vacuum degree curve in the database, outputting process prompt information, where the process prompt information is used to prompt that process fluctuation occurs in the target wafer;

[0077] In response to the user inputting the standard vacuum degree curve corresponding to the target wafer, the database is updated. The standard vacuum degree curve is used to characterize the standard change trend of the vacuum degree of the transfer chamber after the target wafer is transferred into the transfer chamber.

[0078] In this embodiment, process prompt information is output when matching fails to remind the user that process fluctuations occur in the target wafer, that is, the process flow of the target wafer is different from the conventional process flows corresponding to various wafers in the database.

[0079] The user obtains the standard vacuum degree curve of the transfer chamber where the target wafer is located according to the process prompt information, and stores the standard vacuum degree curve in the database to update the database.

[0080] For example, the standard vacuum degree curve can be converted through the standard air pressure curve of the transmission chamber where the target wafer is located, and the standard air pressure curve is used to characterize the standard change of the air pressure of the transmission chamber where the target wafer is located during the vacuum pumping process.

[0081] like Figure 2 As shown, a schematic diagram of a standard pressure curve of a transmission chamber where a target wafer is located is provided. The pressure in the transmission chamber where the target wafer is located decreases with time until it finally stabilizes. Specifically, the standard pressure curve includes four stages.

[0082] The first stage 201, in this stage, the gas in the chamber volume is mainly extracted, and the extraction is performed by the front pump or the rough vacuum pump (usually a dry pump). On the actual machine, this part is completed by the machine's high-speed dry pump, and the time is relatively short; when the pressure reaches the molecular pump working range, it enters the second stage 202. In this stage, the molecular pump begins to evacuate, and the gas adsorbed on the surface is mainly extracted; as the pressure continues to drop, the vacuum degree gradually improves, and the gas adsorbed on the surface is gradually extracted, and the third stage 203 is entered; in this stage, the main extraction is the surface outgassing and the internal dissolved gas diffusion. Finally, it enters the fourth stage 204, and the air pressure tends to be stable.

[0083] As an example, the server first matches the collected third vacuum degree curve with each first vacuum degree curve in the database.

[0084] If there is no target first vacuum degree curve matching the third vacuum degree curve in the database, process prompt information is output to indicate that process fluctuations have occurred in the target wafer, wherein the process prompt information includes but is not limited to: wafer number, transfer chamber number, and vacuum degree data.

[0085] Then, in response to the user inputting the standard vacuum degree curve corresponding to the target wafer, the server updates the database and stores the standard vacuum degree curve input by the user in the database.

[0086] Through this embodiment, when there is no target first vacuum degree curve matching the third vacuum degree curve in the database, the database is updated in time according to the standard vacuum degree curve corresponding to the target wafer input by the user. In this way, it is possible to provide a prompt for process fluctuations and help improve the reliability of subsequent database matching.

[0087] As an optional embodiment, before S104, the method for determining the vacuum degree threshold may further include:

[0088] When there is no target first vacuum degree curve matching the third vacuum degree curve in the database, obtaining a first vacuum degree change rate corresponding to the third vacuum degree curve and a second vacuum degree change rate of each first vacuum degree curve corresponding to the current vacuuming time period when the vacuuming operation is performed in the transmission chamber;

[0089] Comparing the first vacuum degree change rate with each second vacuum degree change rate to obtain a vacuum degree comparison result;

[0090] Determine wafer transfer conditions corresponding to the target wafer according to the vacuum degree comparison result;

[0091] When it is determined that the wafer transfer conditions are met, the target wafer is transferred from the transfer chamber to the main vacuum chamber.

[0092] In this embodiment, the first vacuum degree change rate is used to characterize the change of the vacuum degree in the third vacuum degree curve.

[0093] The second vacuum degree change rate is used to characterize the change of the vacuum degree in the first vacuum degree curve during the current vacuum pumping time corresponding to the third vacuum degree curve.

[0094] The vacuum degree comparison result is used to characterize the magnitude relationship between the first vacuum degree change rate and the second vacuum degree change rate.

[0095] Wafer transfer conditions are used to characterize the conditions that need to be met when transferring the target wafer from the transfer chamber to the main vacuum chamber.

[0096] As an example, when there is no target first vacuum degree curve matching the third vacuum degree curve in the database, the server obtains the first vacuum degree change rate corresponding to the third vacuum degree curve in real time.

[0097] Then, according to the current vacuuming duration corresponding to the third vacuum curve, the second vacuum degree change rate of each first vacuum curve under the corresponding current vacuuming duration is extracted from the database. The first vacuum degree change rate of the third vacuum curve is compared with the second vacuum degree change rate of each first vacuum curve to obtain a vacuum degree comparison result.

[0098] Finally, according to the vacuum comparison result and the preset wafer transfer condition judgment rule, it is determined whether the target wafer meets the wafer transfer condition. If it is determined that the wafer transfer condition is met, the wafer transfer device is started to transfer the target wafer from the transfer chamber to the main vacuum chamber.

[0099] Optionally, the vacuum degree comparison result may include two results: the first vacuum degree change rate is greater than each second vacuum degree change rate, and the first vacuum degree change rate is less than each second vacuum degree change rate.

[0100] When the first vacuum degree change rate is greater than each second vacuum degree change rate, it can be determined that the vacuum pumping speed of the transmission chamber where the target wafer is located is greater than the vacuum pumping speed of the transmission chamber where each wafer in the database is located. The wafer transfer condition can be set as: the time length of the target wafer in the transmission chamber reaches the shortest transfer time among the transfer times corresponding to each first vacuum degree curve in the database.

[0101] When the first vacuum degree change rate is less than each second vacuum degree change rate, it can be determined that the vacuum pumping speed of the transfer chamber where the target wafer is located is less than the vacuum pumping speed of the transfer chamber where each wafer in the database is located. The wafer transfer condition can be set as: the time length of the target wafer in the transfer chamber reaches a preset multiple of the longest transfer time among the transfer times corresponding to each first vacuum degree curve in the database.

[0102] Through this embodiment, a method for determining wafer transfer conditions by comparing vacuum degree change rates is provided when there is no target first vacuum degree curve matching the third vacuum degree curve in the database. Thus, when the wafer meets the transfer conditions, the wafer is transferred to the main vacuum chamber, which can ensure that each wafer can be smoothly transferred to the main vacuum chamber.

[0103] As an optional embodiment, when the vacuum degree comparison result indicates that the first vacuum degree change rate is greater than each second vacuum degree change rate, the wafer transfer condition is that the time length of the target wafer in the transfer chamber satisfies a preset minimum waiting time;

[0104] When the vacuum degree comparison result indicates that the first vacuum degree change rate is less than each second vacuum degree change rate, the wafer transfer condition is that the vacuum degree of the transfer chamber where the target wafer is located is equal to the vacuum degree of the main vacuum chamber.

[0105] In this embodiment, the shortest waiting time is used to represent the shortest waiting time that the wafer must wait after entering the transfer chamber and before being transferred to the main vacuum chamber.

[0106] As an example, when the first vacuum degree change rate is greater than each second vacuum degree change rate, it can be determined that the vacuum pumping speed of the transfer chamber where the target wafer is located is greater than the vacuum pumping speed of the transfer chamber where each wafer in the database is located.

[0107] That is, in this case, the vacuum degree of the transmission chamber where the target wafer is located can ensure that the transmission requirements are met within a relatively short time, so the wafer transmission conditions are set as follows: the time the target wafer is in the transmission chamber meets the preset shortest waiting time.

[0108] When the first vacuum degree change rate is less than each second vacuum degree change rate, it can be determined that the vacuum pumping speed of the transmission chamber where the target wafer is located is less than the vacuum pumping speed of the transmission chamber where each wafer in the database is located.

[0109] That is, in this case, it takes a long time for the vacuum degree of the transmission chamber where the target wafer is located to ensure that it meets the transmission requirements. Therefore, the wafer transmission condition is set as follows: the vacuum degree of the transmission chamber where the target wafer is located is equal to the vacuum degree of the main vacuum chamber.

[0110] Through this embodiment, corresponding wafer transfer conditions are set according to the magnitude relationship between the first vacuum degree change rate and each second vacuum degree change rate, so that when the wafer transfer conditions are met, the wafers are transferred to the main vacuum chamber, which can ensure that each wafer can be smoothly transferred to the main vacuum chamber.

[0111] As an optional embodiment, the wafer transfer condition is that the vacuum degree of the transfer chamber where the target wafer is located is equal to the vacuum degree of the main vacuum chamber;

[0112] After determining the wafer transfer condition corresponding to the target wafer according to the vacuum degree comparison result, the method for determining the vacuum degree threshold may further include:

[0113] Obtaining the number of wafers in the transmission cavity where the target wafer is located;

[0114] When the number of wafers is only one, the transfer chamber is controlled to be connected with the main vacuum chamber;

[0115] In the case where there are multiple wafers, the moving component is controlled to move the wafers other than the target wafer out of the transfer chamber, and the transfer chamber is controlled to communicate with the main vacuum chamber.

[0116] In this embodiment, the moving component is used to move the wafer. For example, the moving component may be a robot arm.

[0117] The server first detects the number and position of wafers in the transmission cavity through sensors to determine the position of the target wafer and the presence of other wafers in the transmission cavity.

[0118] If the sensor detects that the number of wafers in the transfer chamber is only one, that is, the target wafer is the only wafer, the isolation valve between the transfer chamber and the main vacuum chamber is controlled to open, so that the transfer chamber is connected to the main vacuum chamber.

[0119] If the sensor detects that there are multiple wafers in the transfer chamber, the moving assembly is first controlled to remove the wafers other than the target wafer from the transfer chamber, which can be temporarily stored in other storage locations or sent back to the wafer supply area. Then the isolation valve between the transfer chamber and the main vacuum chamber is controlled to open, so that the transfer chamber is connected to the main vacuum chamber.

[0120] Through this embodiment, the transmission chamber is controlled to communicate with the main vacuum chamber, so that the molecular pumps of the main vacuum chamber and the transmission chamber can perform vacuum pumping together, thereby preventing vacuum fluctuations in the main vacuum chamber and further shortening the vacuum pumping time of the transmission chamber.

[0121] Based on the determination method of the vacuum degree threshold value. Accordingly, the present application also provides a specific embodiment of the device for determining the vacuum degree threshold value.

[0122] like Figure 3 As shown, the vacuum threshold determination device 300 provided in the embodiment of the present application includes a transmission chamber vacuum pumping module 310 , a vacuum acquisition module 320 , a curve matching module 330 and a threshold determination module 340 .

[0123] The transmission cavity vacuuming module 310 is used to perform a vacuuming operation on the transmission cavity after the target wafer is transferred into the transmission cavity of the charged particle beam imaging device;

[0124] A vacuum degree acquisition module 320 is used to acquire the vacuum degree of the transmission chamber at multiple moments during the vacuum pumping operation;

[0125] A curve matching module 330 is used to search for a target first vacuum degree curve that matches the vacuum degree at multiple moments from each first vacuum degree curve in the database, wherein the database includes multiple first vacuum degree curves and corresponding vacuum degree stability values, and each first vacuum degree curve is used to characterize a change trend of the vacuum degree of the transfer chamber after wafers with different degassing amounts are introduced;

[0126] The threshold determination module 340 is used to determine the vacuum degree stability value corresponding to the target first vacuum degree curve as the target vacuum degree threshold of the transfer chamber corresponding to the target wafer.

[0127] As an optional embodiment, after searching the first vacuum degree curves in the database for a target first vacuum degree curve that matches the vacuum degrees at multiple moments, the vacuum degree threshold determination device 300 may further include the following modules:

[0128] A duration acquisition module is used to acquire the duration of fluctuation of the vacuum degree from the start to the time when the vacuum degree reaches stability in the target first vacuum degree curve;

[0129] A cyclic execution module, configured to periodically obtain the vacuum degree of the transmission chamber at multiple moments within a preset period of time when the difference between the fluctuation duration and the current actual vacuuming duration corresponding to the vacuuming operation performed by the transmission chamber is greater than a preset interval duration, until a preset condition is met, thereby obtaining a target second vacuum degree curve;

[0130] The preset condition is that the difference between the current actual vacuuming time of the transmission chamber and the fluctuation time of the second vacuum degree curve is less than or equal to the preset interval time, and the second vacuum degree curve is a first vacuum degree curve in the database that matches the vacuum degrees at multiple moments after the vacuum degree is periodically obtained;

[0131] The threshold determination module 340 is specifically configured to:

[0132] The vacuum degree stability value corresponding to the target second vacuum degree curve is determined as the target vacuum degree threshold value of the transmission cavity corresponding to the target wafer.

[0133] As an optional embodiment, before periodically acquiring the vacuum degree of the transmission chamber at multiple moments within a preset time period, the vacuum degree threshold determination device 300 may further include the following modules:

[0134] The duration determination module is used to determine the duration of a preset period according to the difference between the fluctuation duration and the current actual vacuuming duration, and the duration of the preset period is less than the difference.

[0135] As an optional embodiment, the curve matching module 330 specifically includes the following units:

[0136] A curve fitting unit, used for fitting the vacuum degrees at multiple moments to obtain a third vacuum degree curve of the transmission cavity;

[0137] The curve matching unit is used to search for a target first vacuum degree curve that matches the third vacuum degree curve from each first vacuum degree curve in the database.

[0138] As an optional embodiment, after searching the first vacuum degree curves in the database for a target first vacuum degree curve that matches the vacuum degrees at multiple moments, the vacuum degree threshold determination device 300 may further include the following modules:

[0139] A process prompt module, configured to output process prompt information when there is no target first vacuum degree curve matching the third vacuum degree curve in the database, wherein the process prompt information is used to prompt that a process fluctuation occurs in the target wafer;

[0140] The database updating module is used to update the database in response to the user inputting the standard vacuum curve corresponding to the target wafer, where the standard vacuum curve is used to characterize the standard change trend of the vacuum degree of the transmission chamber after the target wafer is transferred into the transmission chamber.

[0141] As an optional embodiment, before determining the vacuum degree stable value corresponding to the target first vacuum degree curve as the target vacuum degree threshold value of the transfer chamber corresponding to the target wafer, the vacuum degree threshold determination device 300 may further include the following modules:

[0142] A change rate acquisition module, for acquiring, when there is no target first vacuum degree curve matching the third vacuum degree curve in the database, a first vacuum degree change rate corresponding to the third vacuum degree curve and a second vacuum degree change rate corresponding to the current vacuuming time of each first vacuum degree curve in the transmission chamber performing a vacuuming operation;

[0143] A change rate comparison module, used for comparing the first vacuum degree change rate with each second vacuum degree change rate to obtain a vacuum degree comparison result;

[0144] A condition determination module, used to determine the wafer transfer condition corresponding to the target wafer according to the vacuum degree comparison result;

[0145] The wafer transfer module is used to transfer the target wafer from the transmission chamber to the main vacuum chamber when it is determined that the wafer transfer conditions are met.

[0146] As an optional embodiment, the wafer transfer condition is that the vacuum degree of the transfer chamber where the target wafer is located is equal to the vacuum degree of the main vacuum chamber;

[0147] After determining the wafer transfer condition corresponding to the target wafer according to the vacuum comparison result, the vacuum threshold determination device 300 may further include the following modules:

[0148] A data acquisition module, used to acquire the number of wafers in the transmission cavity where the target wafer is located;

[0149] The transfer chamber control module is used to control the transfer chamber to communicate with the main vacuum chamber when the number of wafers is only one;

[0150] The transfer chamber control module is also used to control the moving component to move the wafers other than the target wafer out of the transfer chamber when there are multiple wafers, and to control the transfer chamber to communicate with the main vacuum chamber.

[0151] Based on the determination method of the vacuum degree threshold value. Accordingly, the present application also provides a specific embodiment of the device for determining the vacuum degree threshold value.

[0152] Figure 4 A schematic diagram of the hardware structure of a device for determining a vacuum degree threshold provided in an embodiment of the present application is shown.

[0153] The device for determining the vacuum threshold may include a processor 401 and a memory 402 storing computer program instructions.

[0154] Specifically, the processor 401 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0155] Memory 402 may include a large capacity memory for data or instructions. By way of example and not limitation, memory 402 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, memory 402 may include a removable or non-removable (or fixed) medium. In appropriate cases, memory 402 may be inside or outside an integrated gateway disaster recovery device. In a specific embodiment, memory 302 is a non-volatile solid-state memory.

[0156] The processor 401 reads and executes the computer program instructions stored in the memory 402 to implement any one of the methods for determining the vacuum degree threshold in the above embodiments.

[0157] In one example, the vacuum threshold determination device may further include a communication interface 403 and a bus 410. Figure 4 As shown, the processor 401, the memory 402, and the communication interface 403 are connected via a bus 410 and communicate with each other.

[0158] The communication interface 403 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0159] Bus 410 includes hardware, software or both, and the components of the determination device of the vacuum threshold are coupled to each other. For example and not limitation, the bus may include an accelerated graphics port (AGP) or other graphics bus, an enhanced industrial standard architecture (EISA) bus, a front-side bus (FSB), a hypertransport (HT) interconnect, an industrial standard architecture (ISA) bus, an infinite bandwidth interconnect, a low pin count (LPC) bus, a memory bus, a microchannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standard association local (VLB) bus or other suitable bus or a combination of two or more of these. Where appropriate, bus 410 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the present application considers any suitable bus or interconnect.

[0160] In addition, in combination with the method for determining the vacuum threshold in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any method for determining the vacuum threshold in the above embodiment is implemented.

[0161] In addition, in combination with the method for determining the vacuum degree threshold in the above-mentioned embodiment, the embodiment of the present application may provide a computer program product for implementation. When the instructions in the computer program product are executed by the processor of an electronic device, the electronic device executes the method for determining the vacuum degree threshold provided in any aspect of the above-mentioned embodiment of the present application.

[0162] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0163] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0164] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0165] Aspects of the present disclosure are described above with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0166] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for determining a vacuum threshold, characterized in that: include: After the target wafer is transferred into the transmission cavity of the charged particle beam imaging device, a vacuum operation is performed on the transmission cavity; Acquiring the vacuum degree of the transmission chamber at multiple moments during the process of performing the vacuum pumping operation; Searching for a target first vacuum degree curve that matches the vacuum degrees at the multiple moments from each first vacuum degree curve in a database, wherein the database includes multiple first vacuum degree curves and corresponding vacuum degree stability values, and each first vacuum degree curve is used to characterize a change trend of the vacuum degree of the transfer chamber after wafers with different degassing amounts are introduced; The vacuum degree stability value corresponding to the target first vacuum degree curve is determined as a target vacuum degree threshold value of the transfer chamber corresponding to the target wafer.

2. The method according to claim 1, characterized in that After searching the first vacuum degree curves in the database for a target first vacuum degree curve that matches the vacuum degrees at the multiple moments, the method further includes: Obtaining the fluctuation duration of the vacuum degree from the start to the point where it reaches stability in the target first vacuum degree curve; When the difference between the fluctuation duration and the current actual vacuuming duration corresponding to the vacuuming operation performed by the transmission chamber is greater than the preset interval duration, the vacuum degree of the transmission chamber at multiple moments within a preset period is periodically obtained until a preset condition is met, thereby obtaining a target second vacuum degree curve; The preset condition is that the difference between the current actual vacuuming duration of the transmission chamber and the fluctuation duration of the second vacuum degree curve is less than or equal to the preset interval duration, and the second vacuum degree curve is the first vacuum degree curve in the database that matches the vacuum degrees at the multiple moments after the vacuum degrees are periodically acquired; The step of determining the vacuum degree stability value corresponding to the target first vacuum degree curve as the target vacuum degree threshold value of the transfer chamber corresponding to the target wafer includes: The vacuum degree stability value corresponding to the target second vacuum degree curve is determined as the target vacuum degree threshold value of the transfer chamber corresponding to the target wafer.

3. The method according to claim 2, characterized in that Before periodically acquiring the vacuum degree of the transmission chamber at multiple moments within a preset time period, the method further includes: The duration of the preset period is determined according to the difference between the fluctuation duration and the current actual vacuuming duration, and the duration of the preset period is less than the difference.

4. The method according to any one of claims 1 to 3, characterized in that: The step of searching the first vacuum degree curve in the database for a target first vacuum degree curve that matches the vacuum degrees at the multiple moments includes: Fitting the vacuum degrees at the multiple moments to obtain a third vacuum degree curve of the transmission cavity; A target first vacuum degree curve matching the third vacuum degree curve is searched from each first vacuum degree curve in the database.

5. The method according to claim 4, characterized in that After searching the first vacuum degree curves in the database for a target first vacuum degree curve that matches the vacuum degrees at the multiple moments, the method further includes: When there is no target first vacuum degree curve matching the third vacuum degree curve in the database, outputting process prompt information, wherein the process prompt information is used to prompt that process fluctuations occur in the target wafer; In response to a user inputting a standard vacuum degree curve corresponding to the target wafer, the database is updated, wherein the standard vacuum degree curve is used to characterize a standard change trend of the vacuum degree of the transfer chamber after the target wafer is transferred into the transfer chamber.

6. The method according to claim 4, characterized in that Before determining the vacuum degree stability value corresponding to the target first vacuum degree curve as the target vacuum degree threshold value of the transfer chamber corresponding to the target wafer, the method further includes: When there is no target first vacuum degree curve matching the third vacuum degree curve in the database, obtaining a first vacuum degree change rate corresponding to the third vacuum degree curve and a second vacuum degree change rate corresponding to the current vacuuming time length of each first vacuum degree curve in the transmission chamber when the vacuuming operation is performed; Comparing the first vacuum degree change rate with each of the second vacuum degree change rates to obtain a vacuum degree comparison result; Determining wafer transfer conditions corresponding to the target wafer according to the vacuum degree comparison result; When it is determined that the wafer transfer condition is met, the target wafer is transferred from the transfer chamber to a main vacuum chamber.

7. The method according to claim 6, characterized in that When the vacuum degree comparison result indicates that the first vacuum degree change rate is greater than each of the second vacuum degree change rates, the wafer transfer condition is that the time length of the target wafer in the transfer chamber satisfies a preset minimum waiting time; When the vacuum degree comparison result indicates that the first vacuum degree change rate is less than each of the second vacuum degree change rates, the wafer transfer condition is that the vacuum degree of the transfer chamber where the target wafer is located is equal to the vacuum degree of the main vacuum chamber.

8. The method according to claim 7, characterized in that The wafer transfer condition is that the vacuum degree of the transfer chamber where the target wafer is located is equal to the vacuum degree of the main vacuum chamber; After determining the wafer transfer conditions corresponding to the target wafer according to the vacuum degree comparison result, the method further includes: Obtaining the number of wafers in the transmission cavity where the target wafer is located; When the number of wafers is only one, controlling the transfer chamber to communicate with the main vacuum chamber; In the case that there are multiple wafers, the moving component is controlled to move the wafers other than the target wafer out of the transfer chamber, and the transfer chamber is controlled to communicate with the main vacuum chamber.

9. An electronic device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the method for determining the vacuum degree threshold value according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the method for determining a vacuum degree threshold value according to any one of claims 1 to 8 is implemented.

11. A computer program product, characterized in that When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the method for determining the vacuum degree threshold value according to any one of claims 1 to 8.

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