Arithmetic device, charged particle beam system, and charged particle beam system control method

Abstract

In the present invention, in order to reduce a current adjustment time for current adjustment and an operation of adjusting an electronic beam diameter, an arithmetic device acquires, from a storage device that is set correspondingly to a combination of a range of a current value defining a stable state of a sample current in a charged particle beam device, a range of a waiting time indicating a measurement time for the sample current, and a range of a variation amount defining the range of the stable state of the sample current and that holds a plurality of preset values related to the electron beam diameter, one of the plurality of preset values, and transmits the one of the plurality of preset values to the charged particle beam device. The plurality of preset values are statistically determined on the basis of past achievement data of each combination of the current value, the waiting time, and the variation amount of the charged particle beam device. The arithmetic device acquires respective target values of the current value, the waiting time, and the variation amount that are input from the outside, and acquires, from the storage device, the preset value corresponding to the combination of the range of the current value, the range of the waiting time, and the range of the variation amount which include the respective target values (see figure 4).

Description

Arithmetic device, charged particle beam system, and charged particle beam system control method

[0001] The present invention relates to a computing device, a charged particle beam system, and a method for controlling a charged particle beam system.

[0002] An electron microscope is a device that irradiates a sample with an electron beam, detects signals generated by the sample, and acquires images to inspect, measure, and observe the sample. Among these, a scanning electron microscope (SEM) accelerates an electron beam emitted from an electron source, focuses it into a tiny spot diameter using lenses such as electromagnetic and electrostatic lenses, and irradiates the sample surface while scanning it. The electron beam irradiating the sample is called the primary electron beam (primary electron beam). Signal electrons are emitted from the sample upon incidence of the primary electron beam. By irradiating the sample with the primary electron beam while deflecting and scanning it, and detecting the signal electrons emitted from the sample corresponding to the position irradiated by the primary electron beam, images of fine patterns on the sample can be obtained.

[0003] In recent years, the number of users who operate SEMs continuously for long periods of time has been increasing, leading to an increased demand for automatic imaging functions. Users performing particle analysis or foreign material inspections want to maintain a consistent brightness for particles and foreign materials, so they must confirm that the specimen current (Ip) irradiating the specimen is stable before performing automatic imaging. However, in the case of tungsten SEMs, the filament current (If) and emission current (Ie) are unstable immediately after evacuation and application of high voltage. Therefore, users must wait several tens of minutes for the current to stabilize before starting automatic observation. Users must manually check the current. These multiple manual operations are labor-intensive for users.

[0004] Although there is a function that automates various tasks before automatic imaging by automatically controlling the probe current, the current function uses a value set in the SEM as the initial value of the electron beam diameter irradiated on the sample. After the initial value is set, the current measurement and electron beam diameter adjustment (adjustment operation) are initiated. The end condition is the probe current stabilization, and the user does not know when the adjustment operation will end. Considering the lifespan of the filament, users cannot leave the device unattended for long periods after operation has ended, so they are subjected to the stress of having to frequently check the device to see if the above function has finished.

[0005] For example, Patent Document 1 discloses that the time required for an inspection sequence (operation) of one sample is calculated by adding the focus adjustment time and stage movement time to a separately determined SEM image acquisition time and the inspection time for image and data processing required for the inspection, etc., to calculate the time required for the inspection, including the movement and adjustment of each inspection point.

[0006] Patent Document 2 discloses that a master CD-SEM is used as a reference, and polynomial data is sent from a pattern measurement device via a network so that when another CD-SEM measures the same pattern, the same value as the measurement value of the master device is output.

[0007] Patent Document 3 discloses that, in order to shorten the time required to measure the current value, the current value of the electron beam is measured and the waiting time from the injection of the electron beam until the measured current value becomes stable is recorded.

[0008] Patent Document 4 discloses that the beam size is determined as a condition by measuring the beam diameter during current adjustment operation.

[0009] JP 2021-190407 A JP 2014-145602 A JP 2002-176088 A JP 2002-117794 A

[0010] Currently, current adjustment, one of the functional flows that automates various pre-imaging tasks, uses three parameters: the value of the current to be stabilized (current value), the time to measure the current to determine whether it has stabilized (wait time), and the amount of current fluctuation (fluctuation amount) to determine whether the current is stable or unstable. The electron beam diameter is adjusted until the current is determined to be stable, thereby stabilizing the current. The processing time required for the current to stabilize is directly related to the length of the user's work time. For this reason, many users desire a reduction in this processing time.

[0011] Furthermore, when executing the above function, the user must frequently check whether the operation (adjustment operation) has been completed, which is time-consuming and results in the user being tied down to the device for longer periods of time.

[0012] Furthermore, currently, the results of the functions that automate the various tasks before automatic imaging are not managed in a consolidated manner, so that the result data of adjustment operations cannot be shared between multiple SEMs, and users must manage the setting parameter information for multiple SEMs themselves.

[0013] In view of the above, the present invention proposes, as one aspect, a technique for reducing the time required for current adjustment and electron beam diameter adjustment operations, and a technique for predicting and notifying a user of the completion times of various automated work operations (adjustment operations) before automatic imaging.

[0014] In order to solve the above problems, the present invention proposes an arithmetic device that controls the automation of various tasks performed before imaging in a charged particle beam device, comprising: a memory device that stores a plurality of preset values ​​related to electron beam diameter, the preset values ​​being set corresponding to a combination of a current value range that defines the stable state of the specimen current of the charged particle beam device, a waiting time range that indicates the measurement time of the specimen current, and a variation amount range that defines the stable state range of the specimen current; a processor that acquires one of the plurality of preset values ​​from the memory device and transmits it to the charged particle beam device; and the plurality of preset values ​​are statistically determined based on past performance data for each combination of the current value, the waiting time, and the variation amount of the charged particle beam device, and the processor acquires each target value of the current value, the waiting time, and the variation amount input from outside, and acquires from the memory device the preset value corresponding to a combination of the current value range, the waiting time range, and the variation amount range that includes each target value.

[0015] Further features related to the present disclosure will become apparent from the description and accompanying drawings of this specification, and aspects of the present disclosure may be realized and realized by the elements and combinations of various elements and aspects set forth in the following detailed description and the appended claims.

[0016] The descriptions herein are exemplary and illustrative only and are not intended to limit the scope or application of the present disclosure in any way.

[0017] According to the present invention, the time required for current adjustment is reduced, thereby reducing the user's work time. Furthermore, the user does not need to monitor whether imaging preparation is complete. By sharing data across multiple devices using a single software, the user does not need to set parameters for each device. Furthermore, by sending notifications to the user device via the network, the user can know the completion time in real time.

[0018] 5 is a diagram showing an example of a schematic configuration of a charged particle beam system according to an embodiment of the present invention; FIG. 6 is a diagram showing a main window (GUI: Graphical User Interface) for a user to set parameters, etc., of a function for automating various tasks before automatic imaging according to the present embodiment; FIG. 7 is a flowchart for explaining the operation of general current adjustment; FIG. 8 is a flowchart for explaining current adjustment processing according to the present embodiment; FIG. 9 is a diagram showing an example of the configuration of a table that specifies the number of steps according to setting parameters of current setting; FIG. 10 is a diagram showing an example of the configuration of a table that holds preset values ​​corresponding to each of the 288 patterns shown in FIG. 5; FIG. 11 is a diagram for comparing the time required for conventional current adjustment with the time required for current adjustment when preset values ​​are set; FIG. 12 is a sequence diagram showing an example of processing that is executed when data is shared between SEMs; FIG. 13 is a diagram showing an overview of a function that calculates (predicts) and presents the end time of automation processing of various tasks before automatic imaging processing; FIG. 14 is a diagram (table) for explaining a method for calculating (predicting) the end time of automation processing of various tasks before automatic imaging processing; FIG. 15 is a diagram showing the sequence of a process for notifying an end time (predicted value) and a process for notifying an actual end.

[0019] An embodiment of the present invention relates to an electron beam application device such as an electron microscope that uses an electron beam to acquire images of a sample for inspection, measurement, observation, etc., and a method for reducing the processing time of various automated work operations performed by a user before automatic imaging of the electron microscope, etc. More specifically, this embodiment relates to reducing the current adjustment time by setting a preset value that is close to a target electron beam diameter as an initial value based on, for example, three parameters (current value, waiting time, and fluctuation amount) and past performance data, and starting adjustment of the current and electron beam diameter. This embodiment also relates to calculating a predicted completion time of various automated work operations (adjustment operations) before automatic imaging based on, for example, acceleration voltage, vacuum level, convergence conditions, electron beam diameter, product model, etc., and providing the user with the predicted completion time.

[0020] <Overall Configuration of Charged Particle Beam System> Fig. 1 is a diagram showing an example of the schematic configuration of a charged particle beam system according to an embodiment of the present invention. The charged particle beam system according to this embodiment includes a plurality of charged particle beam devices (SEMs) 1 to k (k = 1, 2, ..., n: n is a positive natural number), a computer 200 that controls each of the charged particle beam devices 1 to k, and a management server 400. The computer 200 and the management server 400 are connected to each other via a network 300 so as to be able to communicate with each other.

[0021] Each of the charged particle beam devices 1 to k includes an electron microscope 100, a control device 120, and power supply devices (power supplies) 121 and 122. The calculator 200 can be configured using a computer, and includes a function for automating various tasks before automatic imaging (corresponding to an automated processing control program described below).

[0022] In the electron microscope 100, an electron beam (electron beam) 103 is irradiated onto a sample. The electron microscope 100 outputs a detection signal obtained based on the irradiation of the electron beam 103. The charged particle beam device 1 includes components necessary for forming a signal waveform and an image based on the detection signal from the electron microscope 100. First, an example of the electron microscope 100 will be specifically described with reference to FIG. 1 .

[0023] An electron beam 103 extracted from an electron source 101 by an extraction electrode 102 is accelerated by an acceleration electrode (not shown). The accelerated electron beam 103 is focused by a condenser lens 104, which is a type of converging lens. The focused electron beam 103 is scanned one-dimensionally or two-dimensionally over a sample 108 by a scanning electrode 105. The electron beam 103 is decelerated by a negative voltage applied to an electrode built into a stage (sample holder) 109, and is focused by the lens action of an objective lens 106, and is irradiated onto the sample 108.

[0024] Secondary electrons 110 generated by the sample 108 are reflected by a reflector 112 and detected by a detector 113 as electrons 111. The control device 120 controls the irradiation of the electron beam 103 onto the sample 108 and generates and manages captured images by detecting the electrons 111 with the detector 113. The control device 120 controls the irradiation of the electron beam 103 onto the sample 108 by controlling each element within the electron microscope 100, a power supply 121 to the stage (sample stage) 109, and a power supply 122 to the extraction electrode 102. Another function of the control device 120 is the automation of various tasks (within the computer 200). The automation of various tasks is achieved by the computer 200 executing a program for realizing the function. While the control device 120 and the computer 200 that executes the automation of various tasks are shown as separate components in FIG. 1, they may be executed as separate programs in the same device.

[0025] <Configuration of Function for Automating Various Tasks Before Automatic Imaging> An overview of the function for automating various tasks before automatic imaging will be described with reference to Fig. 2. Fig. 2 is a diagram showing a main window (GUI: Graphical User Interface) for a user to set parameters and the like of the function for automating various tasks before automatic imaging according to this embodiment. The operation of this function can be broadly divided into three: beam adjustment, current adjustment, and brightness adjustment.

[0026] (i) Beam Adjustment First, the sample chamber is controlled to a vacuum state. Then, beam adjustment (beam axis adjustment: beam alignment) is performed. In the beam adjustment operation, the computer 200 sets the acceleration voltage and electron beam diameter instructed in advance by parameter setting in the setting electron microscope 100. Then, the computer 200 moves the stage 109 to the stage setting position for beam adjustment via the control device 120. The computer 200 waits for, for example, five minutes, and then performs auto beam adjustment (ABA (Auto Beam Alignment)) via the control device 120.

[0027] (ii) Current Adjustment The computer 200 adjusts the current. Fig. 3 is a flowchart for explaining the general operation of current adjustment.

[0028] When the current adjustment operation (the initial value of the electron beam diameter is set by the electron microscope 100) is started (S301), the computer 200 (a processor inside the computer, etc.: not shown) moves the stage to the stage setting position for current adjustment (the sample position for current adjustment) via the control device 120 (S302). The computer 200 then sets the magnification at which current adjustment will be performed and executes autofocus control (AFC) (S303). If the magnification setting during AFC differs from the magnification setting during current adjustment, the computer 200 changes the magnification to the magnification setting during AFC and executes AFC.

[0029] After the AFC is completed, the computer 200 resets the magnification to the current adjustment magnification and measures the specimen current Ip (measures Ip for the set time) (S304→S305).

[0030] Next, the computer 200 determines whether the measured specimen current Ip is stable (S306). Whether the specimen current Ip is stable can be confirmed by checking whether the time during which the specimen current Ip is maintained within the target current value ± the convergence condition % (the target current value and the convergence condition (amount of fluctuation): the values ​​set in FIG. 2 ) in a stable current state has elapsed for the waiting time (minutes).

[0031] If the target value is not met (No in S306), the computer 200 readjusts the electron beam diameter (increases the electron beam spot intensity by a predetermined amount) and measures Ip again (S307→S308).

[0032] The Ip measurement is repeatedly executed (S309 → S307 → S308 → S309 / S309 → S310) until the target value is cleared (until Ip is stabilized).

[0033] (iii) Brightness Adjustment After the current adjustment is completed, the computer 200 moves the stage to the sample (sample position) for brightness adjustment via the control device 120, performs AFC and automatic brightness adjustment (ABC: Auto Brightness Control), displays a message on the GUI indicating that the workflow has ended, and terminates the operation.

[0034] <Function of Providing a Preset Value of Electron Beam Diameter to Reduce Current Adjustment Time> A function of providing a preset value of the electron beam diameter to reduce the current adjustment time and performing current adjustment based on the preset value will be described. FIG. 4 is a flowchart for explaining the current adjustment process according to this embodiment. This current adjustment process is a process that adds a function of providing a preset value to the current adjustment process of the function of automating various tasks before automatic imaging in FIG. 3. Specifically, as shown in FIG. 4, the utility pole adjustment process according to this embodiment has the same contents as FIG. 3 in steps S301 to S310, but includes new steps S401 and S402 between steps S303 and S304.

[0035] After the AFC operation (S303), the calculator 200 executes a process of calculating a preset value of the electron beam diameter (S401) and a process of setting the calculated preset value (S402). By adjusting the current based on the preset value, it is possible to set an electron beam diameter close to the electron beam diameter at which the specimen current Ip stabilizes before measuring it, thereby shortening the current adjustment time. <Method for calculating the preset value of the electron beam diameter>

[0036] A method for calculating the preset value of the electron beam diameter will now be described. The preset value of the electron beam diameter can be calculated by statistically processing the setting parameters (hereinafter also referred to as "execution condition data") used in the current adjustment shown in FIG. 2, namely, "current value," "time," and "variation amount," and past performance data. For example, the average value (e.g., simple average, weighted average, geometric mean, harmonic mean, or root mean square average) of past performance data for each set of setting parameters may be calculated, and this may be used as the preset value. The initial value of the preset value may be a value set at the time of shipment. In this case, the manufacturer may statistically process current values ​​corresponding to typical execution results for each of the parameter sets in the current adjustment process to determine the initial value and set it for each of the charged particle beam devices 1 to k. The initially set preset value may be updated each time the user uses the electron microscope 100, or a new preset value may be calculated by performing statistical processing again when a predetermined number of data points have been collected.

[0037] FIG. 5 shows an example of a table that defines the number of steps corresponding to the current setting parameters. In FIG. 5, the parameters provided correspond to "current value," "waiting time ("time" in FIG. 2)," and "fluctuation amount," corresponding to those in FIG. 2. The number of steps is determined for each parameter, and the details are set for each parameter. For example, for "current value," a total of eight steps are provided, ranging from less than 0.5 nA to 500.0 nA or greater and 1250.0 nA or less (the range of current values ​​that defines the stable state of the specimen current). Such steps are provided for "waiting time" (the range of waiting time indicating the measurement time of the specimen current) and "fluctuation amount" (the range of fluctuation that defines the stable state of the specimen current). According to the steps for each parameter in FIG. 5, 8 × 6 × 6 = 288 patterns of conditions (automatic imaging conditions) are provided, and the preset value of the electron beam diameter (spot intensity) corresponding to each automatic imaging condition is statistically determined.

[0038] FIG. 6 is a diagram showing an example of the configuration of a table that holds preset values ​​corresponding to each of the 288 patterns shown in FIG. 5 . This table is stored, for example, in a storage device (not shown) of the computer 200. In FIG. 6 , the "No." in FIG. 6 is determined based on the current adjustment setting parameters and the "step" in FIG. 5 , and the preset value of the electron beam diameter (spot intensity) can be determined (derived). For example, if the current value is "5.0 nA," the waiting time is "5.0 min," and the fluctuation amount is "1%, "No." for the current adjustment setting parameters corresponding to the step in FIG. 5 is "421 (current value: step 4, waiting time: step 2, fluctuation amount: step 1)." Therefore, from FIG. 6 , the preset value of the electron beam diameter is determined to be "d (actually given as a numerical value)."

[0039] <Adjustment time reduced by providing a preset value for the electron beam diameter: technical effect of providing a preset value> The adjustment time reduced by providing a preset value for the electron beam diameter will be described with reference to the drawings. Figure 7 is a diagram for comparing the time required for conventional current adjustment with the time required for current adjustment when a preset value is set.

[0040] 7, by calculating the preset value of the electron beam diameter, the number of times the electron beam diameter needs to be readjusted can be reduced. The reduced number of times the electron beam diameter needs to be readjusted and the waiting time for current measurement are the time that can be reduced by the present invention.

[0041] Specifically, the electron beam diameter value at which the current stabilizes is set to "20.4," the electron beam diameter (set value) displayed on the SEM GUI is set to "20.0," the preset value derived from the above parameters is set to "20.2," and the current adjustment time (wait time) is set to "10 min." Figure 7 shows that by setting the preset value, the number of readjustments and measurements of the electron beam diameter is reduced by two, which means that the number of readjustments and measurements can be reduced, and therefore the current adjustment time is shortened by approximately 20 minutes.

[0042] <Data Sharing Between SEMs with a Function for Automating Various Operations Before Automatic Imaging> Data sharing between SEMs with a function for automating various operations before automatic imaging will be described. Fig. 8 is a sequence diagram showing an example of processing executed when data is shared between SEMs.

[0043] According to the data supply function of this embodiment, for example, the parameter conditions used in SEM1 can be registered via a network in a control program that automates various tasks before common automatic imaging, allowing settings to be shared similarly with SEM2.

[0044] 8, in sequence (i), the computer 200 sends a command to the SEM 1 to execute an automated process. In response to the command, the SEM 1 executes the automated process (at least one of beam adjustment, current adjustment, and brightness adjustment). In sequence (ii), the SEM 1 sends a command to the computer 200 requesting registration of execution condition data (current value, time, and amount of variation in the automated process).

[0045] In sequences (iii) and (iv), in response to the registration request received from SEM1, computer 200 transmits the execution condition data to management server 400 via network 300. Management server 400 registers the execution condition data in a database (not shown) as automation usage data.

[0046] In sequence (v), SEM2 sends a request to computer 200 to obtain execution condition data for automation processing by SEM1, and in sequences (vi) and (vii), computer 200 requests management server 400 to send registration data via network 300.

[0047] In sequences (viii) and (ix), the management server 400 responds to the request for transmission of execution condition data from SEM 1 , obtains the corresponding execution condition data from the database, and transmits it to the computer 200 via the network 300 .

[0048] In sequence (x), the computer 200 provides the acquired execution condition data to the SEM 2 .

[0049] As described above, it is possible to use the SEM 2, which has different execution conditions for automating the various operations before automatic imaging in the SEM 1, from the SEM 1.

[0050] <Regarding the function of presenting the end time (predicted value) of the automated process before the automatic imaging process> The function of presenting the end time (predicted value) of the automated process before the automatic imaging process will be described with reference to Fig. 9 and Fig. 10. Fig. 9 is a diagram showing an overview of the function of calculating (predicting) and presenting the end time of the automated process of various tasks before the automatic imaging process. Fig. 10 is a diagram (table) for explaining the method of calculating (predicting) the end time of the automated process.

[0051] (Comparison with Existing Systems) As shown in Figure 9, existing systems only realize the automation function for various tasks before automatic imaging, but do not have a function for presenting the completion time. In contrast, the system according to this embodiment not only has the automation function for various tasks before automatic imaging, but also has a function for calculating (predicting) and presenting the completion time of the automation function. The calculation (prediction) of the completion time is performed based on each parameter of the function that automates various tasks before automatic imaging. The method for calculating the completion time will be described next with reference to Figure 10.

[0052] (Details of Calculation (Prediction) of Completion Times of Automated Processing of Various Tasks Before Automatic Imaging Processing) Fig. 10 is a table showing data for statistically calculating completion times. The parameters used to predict the completion times are roughly divided into four categories.

[0053] The first item is a parameter that varies significantly depending on the SEM product. The item names "Product," "Vacuum," and "Filament Setting" correspond to the classification of "1" in the classification category. Because the time required for automated beam adjustment varies depending on the performance of the electron gun for each electron microscope (SEM), "Product" information is necessary for predicting the completion time. Furthermore, "Vacuum" information is necessary for estimating the time required to achieve a vacuum. Achieving a higher vacuum than the specified vacuum takes longer than achieving a lower vacuum. "Filament Setting" is information equivalent to the setting value for emitting the electron gun beam. Because the filament setting differs for each SEM model, the intensity of the electron beam changes accordingly. Furthermore, because this intensity is directly linked to current stability, the completion time also changes depending on the filament setting.

[0054] The second item is a parameter that affects the time required for beam adjustment. The item names "Beam Adjustment," "Stage Position During Beam Adjustment," "Acceleration Voltage," and "Electron Beam Diameter" are classified as category "2." "Beam Adjustment" is information indicating whether or not beam adjustment is performed. Whether or not beam adjustment is performed can be specified using the checkbox in the GUI shown in Figure 2. If beam adjustment is performed, the time required for it is added to the end time calculation. "Beam Adjustment Stage Position" is information indicating the distance from the current beam position to the stage position when beam adjustment is performed. The time required for stage movement is added to the end time calculation. "Acceleration Voltage" is information on the acceleration voltage value used for beam irradiation. The time required to achieve the desired acceleration voltage is added to the end time calculation. "Electron Beam Diameter" is information indicating the diameter of the emitted electron beam. The time required to achieve the desired electron beam diameter is added to the end time calculation.

[0055] The third item is a parameter that affects the time required for current adjustment. The case items "Current Adjustment," "Current Adjustment Stage Position," "Wait Time" when the electron beam diameter is readjusted, and the target "Convergence Condition," "Current Value," "Current Adjustment Magnification," and "Current Adjustment Autofocus / Magnification" are applicable to the classification item "3." "Current Adjustment" is information indicating whether or not current adjustment is performed. Whether or not current adjustment is performed can be specified using a checkbox in the GUI shown in Figure 2. If current adjustment is performed, the time required for the adjustment is added to the end time calculation. "Current Adjustment Stage Position" is information indicating the distance from the current beam position to the stage position when current adjustment is performed. The time required for stage movement is added to the end time calculation. "Wait Time," "Convergence Condition," and "Current Value" are parameters used in current adjustment and are specified by the user in the GUI shown in Figure 2. When current adjustment is OFF, the "Wait Time" information is not taken into account in the end time calculation. If the "Convergence Condition" is strict, the adjustment time is longer, resulting in a longer end time. For example, the time required to achieve a convergence condition within 5% can be calculated statistically based on past data, just as with calculating a preset value. The "current value" information is used to calculate the time required to achieve the set current value (for example, information on typical times required to achieve each current value, such as 1.5 A, is tabulated and stored in memory), and this is added to the end time calculation. The "current adjustment magnification" is information corresponding to the magnification (imaging magnification) desired by the user when capturing an image. The "current adjustment autofocus / magnification" is information on the magnification of the autofocus adjustment performed after the current adjustment. The current adjustment magnification item has little impact on the end time calculation.

[0056] The fourth item is a parameter that affects the time required for brightness adjustment. The items "brightness adjustment," "brightness adjustment stage position," "brightness adjustment magnification," and "brightness adjustment autofocus adjustment / magnification" correspond to the classification item "4." "Brightness adjustment" is information indicating whether brightness adjustment is performed. Whether brightness adjustment is performed can be specified using the checkbox in the GUI shown in Figure 2. If brightness adjustment is performed, the time required for this is added to the end time calculation. "brightness adjustment stage position" is information indicating the distance from the current position of the beam to the stage position when brightness adjustment is performed. The time required for stage movement is added to the end time calculation. "brightness adjustment magnification" is information corresponding to the magnification desired by the user when capturing an image (imaging magnification). "brightness adjustment autofocus / magnification" is information regarding the magnification of the autofocus adjustment performed after brightness adjustment. Note that the brightness adjustment magnification item has little impact on the end time calculation.

[0057] The completion time is calculated for each condition based on the performance data for each item. For example, for Product A, the statistical completion time when beam adjustment and current adjustment are performed without brightness adjustment can be calculated (predicted) using data for No. 1 and No. 3 corresponding to "Product A." Considering the GUI settings in FIG. 2, "Beam Adjustment," "Current Adjustment," and "Brightness Adjustment" are all ON (all checkboxes are checked), so Case No. 1 in FIG. 10 applies. Therefore, the completion time is calculated and displayed by accumulating the time required for each item in Case No. 1.

[0058] In this example (product A), "beam adjustment," "current adjustment," and "brightness adjustment" are used as the narrowing down elements, but elements other than "end time" in Fig. 10 can also be used as the narrowing down element. In this way, the cases used for calculating the end time are narrowed down based on the execution conditions, and the end time of the corresponding performance data is extracted and output, or the end time may be statistically calculated (predicted) and output by calculating the average value from multiple performance data.

[0059] The computer 200 statistically calculates (predicts) the completion times of the various automated processes for product A prior to the automatic imaging process, and presents these to the users of SEM1 and SEM2. Alternatively, the completion time calculation (prediction) function may be provided in the management server 400, and the completion times of the automated processes statistically calculated by the management server 400 may be presented to the user. In this case, the management server 400 may be configured to have a function for storing post-execution data and execution conditions in a database in addition to the statistical completion time calculation function.

[0060] <Regarding Completion Notification of Function for Automating Various Tasks Before Automatic Imaging> The following describes the function for notifying the completion time (predicted value) of the automation process for various tasks before automatic imaging processing, and the function for notifying the actual completion. Fig. 11 is a diagram showing the sequence of the process for notifying the completion time (predicted value) and the process for notifying the actual completion.

[0061] 11 , in sequence (i), a connection is established between the SEM 1 and the computer (automation processing control program) 200 so that they can communicate with each other. In sequence (ii), the user sets configuration parameters on the display screen of the computer 200, and the computer 200 requests the management server 400 to calculate and transmit an end time (predicted value). Note that, although in FIG. 11 , the management server 400 is configured to calculate (predict) the end times of the automation processing of various tasks before the automatic imaging processing, the calculation may also be performed by the computer 200.

[0062] In sequence (iii), the setting parameters are sent from the computer 200 to the management server via the network 300. Thereafter, the management server 400 calculates (predicts) the end time based on the setting parameters.

[0063] In sequence (iv), the management server 400 transmits the calculated end time (predicted value) to the computer 200 via the network 300. In sequence (v), the computer 200 receives the end time (predicted value) data transmitted from the management server 400 via the network 300.

[0064] In sequence (vi), the computer 200 displays the end time (predicted value) on the display screen (GUI), and in sequence (vi), sends a command to the SEM 1 to execute the automated process. Note that the end time (predicted value) may be provided to the user device 500 instead of the computer 200.

[0065] In sequence (vii), SEM1 transmits a command (completion notification command) to notify the computer 200 of the completion of the automation process of the various tasks described above. In sequence (viii), in response to the completion notification command from SEM1, computer 200 transmits the executed setting parameters and the completion time (actual time) to management server 400 via network 300.

[0066] In sequence (ix), the management server 400 accumulates data on the setting parameters used in SEM1 and the actual completion time (processing time). The accumulated data is stored in a storage device (not shown), for example, according to the data format of FIG. 10. By comparing the completion time (predicted value) with the actual processing time, it is possible to improve the accuracy of the completion time (predicted value) provided to the user thereafter.

[0067] In sequence (x), the computer 200 transmits a completion notification to the user device 500 (the device of the user who inputted the setting parameters into the computer 200 or a pre-designated user device) via the network 300. This allows the user to know the completion of the automated processing in real time while working on another task at a location away from the electron microscope 100. The completion notification may include, for example, the current filament life of the SEM 1 or execution data. The filament life can be estimated from the measured value of the filament voltage or filament current (estimating the filament life from the measured value of the filament current is disclosed, for example, in WO 2020 / 161795). This allows the user to know the status of the SEM 1 and manage information about the automated processing before automatic imaging.

[0068] <Other> The functions of the present embodiment can also be realized by software program code. In this case, a storage medium on which the program code is recorded is provided to a system or device, and the computer (or CPU or MPU) of the system or device reads the program code stored in the storage medium. In this case, the program code read from the storage medium itself realizes the functions of the above-described embodiment, and the program code itself and the storage medium on which it is stored constitute the present invention. Examples of storage media for providing such program code include flexible disks, CD-ROMs, DVD-ROMs, hard disks, optical disks, magneto-optical disks, CD-Rs, magnetic tape, non-volatile memory cards, and ROMs.

[0069] In addition, an operating system (OS) running on a computer may perform some or all of the actual processing based on the instructions of the program code, and the functions of the above-described embodiments may be realized by this processing.Furthermore, after the program code is read from a storage medium and written to a memory on the computer, a CPU of the computer may perform some or all of the actual processing based on the instructions of the program code, and the functions of the above-described embodiments may be realized by this processing.

[0070] Furthermore, the program code of the software that realizes the functions of this embodiment may be distributed via a network and stored in a storage means such as a hard disk or memory of the system or device, or in a storage medium such as a CD-RW or CD-R, so that when in use, the computer (or CPU or MPU) of the system or device reads and executes the program code stored in the storage means or storage medium.

[0071] The processes and techniques described herein are not inherently related to any specific device and can be implemented by a combination of components. Various types of general-purpose devices can also be added. A dedicated device may be constructed to perform the functions of this embodiment. Various functions can also be formed by appropriately combining multiple components disclosed in this embodiment. For example, some components may be omitted from all the components described in this embodiment, or components with different configurations or functional examples may be appropriately combined.

[0072] The present invention is described herein with reference to specific examples, which are in all respects illustrative and not limiting. Those skilled in the art will recognize that there are numerous combinations of hardware, software, and firmware suitable for implementing the present invention. For example, the described software can be implemented in a wide variety of programming or scripting languages, such as assembler, C / C++, Perl, Shell, PHP, Java, etc.

[0073] Furthermore, in the above-described embodiment, the control lines and information lines are those that are considered necessary for the explanation, and not all control lines and information lines in the product are necessarily shown. All components may be interconnected.

[0074] In addition, other implementations of the present invention will become apparent to those skilled in the art from consideration of the present embodiments and examples. The specification and examples are exemplary only, with the scope and spirit of the invention being indicated by the following claims.

[0075] REFERENCE SIGNS LIST 1 Charged particle beam device (SEM1) 2 Charged particle beam device (SEM2) 100 Electron microscope 200 Computer 300 Network 400 Management server 500 User device

Claims

1. An arithmetic device that controls the automation of various pre-imaging tasks in a charged particle beam device, comprising: a storage device that stores a plurality of preset values ​​related to electron beam diameter, the preset values ​​being set corresponding to a combination of a current value range that defines the stable state of the specimen current of the charged particle beam device, a waiting time range that indicates the measurement time of the specimen current, and a variation amount range that defines the stable state range of the specimen current; a processor that acquires one of the plurality of preset values ​​from the storage device and transmits it to the charged particle beam device; the plurality of preset values ​​being statistically determined based on past performance data for each combination of the current value, waiting time, and variation amount of the charged particle beam device; and the processor acquires each target value of the current value, waiting time, and variation amount input from outside, and acquires from the storage device the preset value corresponding to the combination of the current value range, waiting time range, and variation amount range that includes each target value.

2. A charged particle beam system comprising: the arithmetic device according to claim 1; and at least one charged particle beam device, wherein the charged particle beam device, having received the preset values ​​corresponding to each of the target values ​​from the arithmetic device, starts a current adjustment process at the electron beam diameter indicated by the preset values, and repeats the current adjustment process until the current value reaches the target value.

3. A charged particle beam system as claimed in claim 2, further comprising a management server connected to the arithmetic device via a network and managing execution condition data for automation processing of various pre-imaging tasks in the at least one charged particle beam device, wherein the management server stores the execution condition data for a first charged particle beam device in a database, and in response to a request for the execution condition data for the first charged particle beam device from a second charged particle beam device different from the first charged particle beam device, acquires the execution condition data for the first charged particle beam device from the database and transmits it to the second charged particle beam device, and the second charged particle beam device executes automation processing of the various pre-imaging tasks based on the execution condition data for the first charged particle beam device.

4. A charged particle beam system as claimed in claim 2, further comprising a management server connected to the arithmetic device via a network and managing execution condition data for the automation processing of the various pre-imaging tasks in the at least one charged particle beam device, wherein the management server receives setting parameters for the at least one charged particle beam device from the arithmetic device, calculates a predicted end time for the automation processing of the various pre-imaging tasks based on the setting parameters and actual data on past processing times for the automation processing of the various pre-imaging tasks, and transmits the predicted end time to the arithmetic device, and the arithmetic device outputs the predicted end time on a display screen.

5. A charged particle beam system according to claim 4, wherein the management server calculates the predicted end time in the charged particle beam device by statistically processing a plurality of pieces of performance data.

6. A charged particle beam system according to claim 4, wherein the arithmetic device transmits a notification of completion of the automation processing of the various pre-imaging tasks in the at least one charged particle beam device to a user device.

7. A charged particle beam system according to claim 6, wherein the arithmetic device transmits actual processing time data of the automated processing to the management server, and the management server registers the actual processing time data in a database.

8. A charged particle beam system according to claim 6, wherein the computing device transmits information regarding the life of a filament included in the at least one charged particle beam device to the user device together with the termination notification.

9. A method for controlling a charged particle beam system using a computer to control automated processing of various pre-imaging tasks in a charged particle beam device, comprising: a step of providing a storage device for storing a plurality of preset values ​​related to electron beam diameter, the preset values ​​being set corresponding to combinations of a current value range that defines the stable state of the specimen current of the charged particle beam device, a waiting time range that indicates the measurement time of the specimen current, and a variation amount range that defines the stable state range of the specimen current; and a step of acquiring one of the plurality of preset values ​​from the storage device and transmitting it to the charged particle beam device, wherein the plurality of preset values ​​are statistically determined based on past performance data for each combination of the current value, the waiting time, and the variation amount of the charged particle beam device, and acquiring one of the plurality of preset values ​​comprises acquiring each target value of the current value, the waiting time, and the variation amount that is input from outside, and acquiring from the storage device the preset value corresponding to the combination of the current value range, the waiting time range, and the variation amount range that includes the each target value.

10. A method for controlling a charged particle beam system according to claim 9, further comprising the steps of: the charged particle beam device receiving the preset values ​​corresponding to each of the target values ​​from the computer, starting a current adjustment process at the electron beam diameter indicated by the preset values, and repeating the current adjustment process until the current value reaches the target value.

11. A method for controlling a charged particle beam system according to claim 10, further comprising the steps of: providing a management server connected to the computer via a network, and managing execution condition data for automation processing of the various pre-imaging tasks in the at least one charged particle beam device; the management server storing the execution condition data for a first charged particle beam device in a database; the management server acquiring the execution condition data for the first charged particle beam device from the database in response to a request for the execution condition data for the first charged particle beam device from a second charged particle beam device different from the first charged particle beam device, and transmitting the execution condition data to the second charged particle beam device; and the second charged particle beam device executing automation processing of the various pre-imaging tasks based on the execution condition data for the first charged particle beam device.

12. A method for controlling a charged particle beam system according to claim 10, further comprising the steps of: providing a management server connected to the computer via a network, and managing execution condition data for the automation processing of the various pre-imaging tasks in the at least one charged particle beam device; the management server receiving setting parameters for the at least one charged particle beam device from the computer, calculating a predicted end time for the automation processing of the various pre-imaging tasks based on the setting parameters and actual data on past processing times for the automation processing of the various pre-imaging tasks, and transmitting the predicted end time to the computer; and the computer outputting the predicted end time on a display screen.

13. A method for controlling a charged particle beam system according to claim 12, further comprising a step in which the management server calculates the predicted end time of the charged particle beam device by statistically processing a plurality of pieces of performance data.

14. A method for controlling a charged particle beam system according to claim 12, further comprising a step in which the computer transmits to a user device a notification of completion of the automation processing of the various pre-imaging tasks in the at least one charged particle beam device.

15. A method for controlling a charged particle beam system according to claim 14, further comprising the steps of: the computer transmitting actual processing time data of the automated processing to the management server; and the management server registering the actual processing time data in a database.

16. A method for controlling a charged particle beam system according to claim 14, further comprising a step in which the computer transmits information regarding the life of a filament included in the at least one charged particle beam device to the user device together with the termination notification.

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