JP5213907B2 - Sample processing equipment - Google Patents

Description

  The present invention relates to a processing method and a processing apparatus using a focused ion beam (FIB).

  An FIB apparatus is used for cross-sectional processing of micro devices and new functional materials, preparation of a sample for a transmission electron microscope, micro machining of micro mechanical parts, and the like (for example, see Patent Document 1). For example, in FIB processing to cut out a sample from a specimen, stage movement for processing different locations on the specimen, stage rotation for processing from different directions, change of beam current and beam diameter, change from sputtering to deposition A plurality of processes including these are required. As a method for sampling processing, a simple processing method in which a desired shape is individually processed at a desired position on a sample under a desired condition, and a process of cutting out one sample by combining a plurality of individual processings are continuously executed. There is a sampling processing method or an automatic processing method in which a plurality of sampling processes are prepared and executed collectively.

Japanese Patent Publication No. 7-71755

  In any of the simple processing method, the sampling processing method, and the automatic processing method, the processing is performed according to the processing procedure set by the operator. Therefore, there is a case where unnecessary movement is forced in view of the mechanism and performance of the apparatus, which causes waste of total machining time and instability of machining accuracy.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a FIB processing method that optimizes the processing order of processing locations scattered on a processing target sample.

  In the FIB processing that requires a plurality of steps, the present invention rearranges the processing order to an appropriate one and executes it to shorten the stage moving distance, reduce the number of stage rotations, and select the type of processing. Realizes a reduction in the number of mechanism switching, shortens the total machining time, and improves machining accuracy.

  That is, the sample processing method according to the present invention is a sample processing method in which a sample held on a stage that can be translated and rotated is irradiated with a focused ion beam from an oblique direction. Dividing into a set of minimum machining units that can be machined without moving the stage, changing the beam type, and changing the machining type, and the current stage and beam from a plurality of unprocessed minimum machining units The method includes a step of searching for a minimum processing unit to be processed next based on a relationship between the type and the state of the processing type, and a step of processing the searched minimum processing unit.

  It is also possible to sequentially search for the minimum processing unit to be processed next, determine only the processing order first, and then process the sample continuously according to the determined order.

  Stage movement includes translation and rotation of the stage. Beam types include rough machining beams with large beam diameter and beam current, medium machining beams with medium diameter and finishing beams with small beam diameter and small current. . Further, the processing types include sputtering and deposition.

  The search for the minimum processing unit to be processed next is performed in consideration of the processing efficiency. Specifically, it is preferable to search for the minimum processing unit that can be processed in the shortest time from the current state as the minimum processing unit to be processed next. Further, the search for the minimum processing unit to be processed next needs to be performed in consideration of the preconditions for starting the processing of each minimum processing unit.

The sample processing method according to the present invention is also a sample processing method for processing a sample held on a translatable and rotatable stage by irradiating a focused ion beam from an oblique direction. Steps to divide into a set of minimum processing units that can be processed without changing the stage, changing the beam type and changing the processing type, information on the processing location, information on the beam irradiation direction for each minimum processing unit, Create a machining information table that describes information about beam type and information about machining type, and set penalties for translation of stage, stage rotation, beam type change, and machining type change. The current stage, beam type and machining type status against the machining information table, A small minimum feature units of penalty upon transition from state, characterized in that it comprises the steps of selecting as the next processing. Normally, the smallest machining unit with the smallest penalty is selected as the next machining.
It is preferable that the processing information includes a flag indicating whether or not the processing has been completed and information on a precondition for starting the processing.

  The sample processing method according to the present invention is a sample processing method in which a sample held on a stage that can be translated and rotated is irradiated with a focused ion beam from an oblique direction, and the sample is processed under the same preconditions. The stage is divided into a set of minimum processing units that can be processed without changing the stage, changing the beam type, and changing the processing type, information on the processing location, information on the beam irradiation direction, and beam type for each minimum processing unit. A step of creating a machining information table describing information including information on the machining type and information on the machining type, and based on the coefficients given to the stage movement, stage rotation, beam type change and machining type change, respectively. The current stage, beam type and machining type status are compared with the machining information table, and each minimum machining is checked from the current status. Characterized in that it comprises calculating a total cost of transition to position, and selecting a smaller minimum processing unit of the total cost as the next processing. Normally, the smallest machining unit with the smallest total cost is selected as the next machining.

  It is preferable to include information on the preconditions for starting machining of each minimum machining unit in the machining information table, and to calculate the total cost for the minimum machining unit that satisfies the preconditions.

  The coefficient may be derived on the basis of data stored for the time required when the stage is moved, the stage is rotated, the beam type is changed, and the processing type is changed. Alternatively, a device set in advance based on the specifications of the apparatus may be used.

  According to the present invention, it is possible to perform processing on a more efficient route by matching the mechanism switching time of the FIB apparatus and the stage alignment time. Furthermore, it is possible to increase the effectiveness of route selection by measuring the time for mechanism switching and stage alignment, and saving and reusing this time. Since the number of mechanism switching times is reduced, machining accuracy is improved. Even if the stage is temporarily moved during the processing to readjust the beam, and the beam is moved to a location different from the processing location, the most efficient processing location from the current location different from the processing location by the processing resumption instruction It is possible to resume processing from the beginning.

  According to the present invention, the useless movement of the FIB processing apparatus and the number of switching mechanisms can be reduced, and the total processing time can be shortened and the processing accuracy can be improved.

The schematic diagram which shows the structural example of the FIB processing apparatus by this invention. The figure which shows an example of a recipe execution operation screen. The figure which showed the typical process site | part for cutting out a sample from a sample. The figure which showed the sample cut out from the sample in three dimensions. The flowchart which showed the processing procedure for sampling. The figure explaining the example of a process information table. The figure which shows the example of a priority definition table. The schematic diagram which shows the positional relationship of two samples on a sample. Flow when processing multiple samples in an appropriate processing order Explanatory drawing of the method of parameterizing in order to hold | maintain a mechanism switching time in a database, and to derive | lead-out the suitable processing order at the time of the next process. The figure explaining the example of a process of a state monitoring program. The flowchart which shows the process example of a recipe execution program.

Embodiments of the present invention will be described below with reference to the drawings.
Data relating to the processing procedure and conditions for the sample to be processed is called a recipe, and the operator creates a new recipe or reuses an already created recipe to give a processing instruction to the apparatus. When the FIB apparatus executes a recipe in accordance with an instruction from an operator, the FIB apparatus first interprets the contents of the recipe. At this time, the minimum processing that is performed by deflecting and irradiating the focused ion beam to the desired range is regarded as one processing location (minimum processing unit), and the recipe is subdivided into a set of processing locations. And a machining information table is created for each machining location. The processing information table includes a processed flag, a processing precondition, a processing location (coordinates on the sample), a processing direction, a focused ion beam type (rough processing, medium processing, finishing processing), and a processing type (sputtering or data processing). Position) information. In the recipe interpretation, the current apparatus state is obtained and collated with each processing information table to determine the most efficient processing point in view of the current apparatus state. However, since individual processing may have a context with other processing, it is excluded from selection candidates if it does not meet the preconditions. When the machining of the highest priority machining location at that time determined in this way is completed, the machined flag of the machining information table at that location is turned on. In this way, the machining process is performed on all the machining points while deriving an appropriate machining point from the current machining point state and the contents of the machining information table.

  By giving a priority of comparison to the processing information items themselves, it is possible to preferentially select processing in which the prioritized items have the same conditions as the current one. In addition, a coefficient that represents the complexity when moving to machining for each item is prepared, the degree of deviation from the current state is represented using this coefficient, and the machining location with the smallest total may be the next candidate. it can. For the coefficient at this time, a method for storing in the machining information table and a method for external reference using items as keys are prepared.

  The timing for determining the processing order is prepared by a batch method that determines a processing schedule in a batch at the start of a recipe and a sequential method that determines the next processing candidate while processing. The former has the advantage that the operator can be notified in advance of the schedule before processing, and the latter can flexibly handle exception processing during processing, such as the need for stage movement or beam adjustment by the operator. There are advantages you can do. The function of dynamically deriving the next machining location suitable for the current state is implemented as software executed by a computer.

  FIG. 1 is a schematic diagram showing a configuration example of a FIB processing apparatus according to the present invention. A focused ion beam (FIB) 2 inclined by 45 ° from a direction perpendicular to the surface of the sample to be processed passes through the aperture 5, is focused by the focused ion beam optical system 6, and is irradiated onto the sample 1. The sample stage on which the sample 1 is mounted includes an XYZ stage 3 that can move in three axes of X, Y, and Z, and an R stage 4 that can rotate the sample in the horizontal direction. It is possible to observe from an angle of elevation of 45 degrees when viewed from the sample, and to process with a focused ion beam.

  The sample is observed by detecting secondary charged particles generated from the sample with the detector 8 and displaying the sample image on the display device 13 via the computer 10. While observing the sample image displayed on the display device 13, the observation region and processing region of the sample are determined, and the focused ion beam optical system 6 and the aperture 5 are controlled via the interlocked beam deflection control device 14. Do. Above the XYZ stage 3, a Z sensor 16 for detecting the height of the sample on the stage is provided. The computer 10 is equipped with a device control program that controls the entire device, a state monitoring program that recognizes the current device state, and a recipe execution program that performs processing and control related to the recipe.

  For processing, sputtering is performed to irradiate the sample 1 by irradiating the ion beam 2 focused from the focused ion beam optical system 6 to an arbitrary position of the sample 1, and tungsten compound gas or carbon compound gas is used as a gas source. There is a deposition in which a gas is released to the vicinity of the sample by the position gun 7 to form a film on the sample 1. Processing setting is performed by inputting processing setting information from the information input device 11 while viewing the sample image displayed on the display device 13. That is, while observing the secondary electron image of the imaged sample, the sample stages 3 and 4 are moved, the deflection area of the beam 2 is designated, and the figure displayed superimposed on the sample image of the display device 13 is used. To determine where to hit the beam. Once the processing region is determined, processing is performed by specifying conditions such as the beam, diameter, time, sputtering / deposition used for processing.

  As a feature of this FIB processing apparatus, there is a function of cutting out a small piece from a sample using processing by a focused ion beam called micro sampling. This micro-sampling is a function of cutting the periphery of a sample to be taken out by sputtering, adhering the probe 9 to the sample by deposition, and transferring it to a dedicated table called a cartridge 15.

  In this apparatus, a processing procedure called a recipe is created by using the display device 13 and the information input device 11 to preliminarily determine what processing is performed at what location on the sample and under what conditions, and is stored in the storage device 12. can do.

  FIG. 2 is a diagram illustrating an example of a recipe execution operation screen 20 displayed on the screen display device 13 when executing a recipe. As a processing method, there is “OnebyOne” in which processing is performed while sequentially deriving an appropriate processing location, or “Batch” in which all processing routes are derived at the time of processing processing start instruction. The operator selects a processing method using the menu button 21 on the recipe execution operation screen 20. When the menu button 22 for selecting a mechanism operation database is used, “Default” using a mechanism operation database defined in advance by the apparatus and “Flexible” using a mechanism operation database reflecting a result of operating the apparatus are used. Either can be selected. The “TopStart” button 23 is an instruction button for instructing execution from the beginning of the recipe, and the “Continue” button 24 is an instruction for instructing to resume from when the recipe is stopped halfway. The “Pause” button 25 is a button for interrupting the recipe halfway, and can be resumed by the “Continue” button 24. The “Stop” button 26 is a button for completely stopping the recipe, and after the recipe is stopped by pressing this button, the recipe processing by the “Continue” button 24 cannot be continued.

  First, using FIG. 3 to FIG. 5, a description will be given of a processing process when one sample is cut out from a sample using the microsampling function of the FIB processing apparatus shown in FIG. 1. FIG. 3 is a diagram showing a typical processing site for cutting out a sample from a sample. FIG. 3 (a) is a schematic plan view of a sample processing region of the sample, and FIG. 3 (b) is an AA cross-sectional view thereof. 3 (c) is a BB cross-sectional view. FIG. 4 is a diagram three-dimensionally showing a sample cut out from the sample. FIG. 5 is a flowchart showing a processing procedure for sampling.

  In FIG. 3, reference numeral 31 denotes a marker that serves as a guide when the sample 39 is processed into a thin film, and this vertical direction is the observation surface 38. The marker 31 is marked by utilizing a sputtering phenomenon caused by irradiation of the focused ion beam 2 onto the sample surface. Reference numeral 36 denotes a metal deposition film for detecting electrical continuity when the probe is bonded. The fact that the sample connected to the probe is separated from the sample and the electrical continuity between the sample and the sample body is lost is used to detect that the sample has been removed from the sample. Reference numeral 32 denotes a deposition film for protecting the sample surface. When the sample is cut, the film has a role of preventing scraps of the sample from being accumulated on the sample surface due to the peripheral processing of the sample or preventing the sample surface from being scraped off due to the influence of the nearby processing. The large horizontal groove 33, the small horizontal groove 34, and the vertical groove 35, which are the three sides, are processed using the vertical irradiation angle of the focused ion beam. The oblique grooves 37 are cut using the fact that the focused ion beam is inclined 45 °. Since the beam irradiation direction is fixed, when cutting one sample, the irradiation direction is changed by rotating the stage. In order to perform one sampling in this way, it is necessary to consider processing around the sample, deposition, movement of the stage, rotation, change of the beam used, and the like. In some cases, steps such as beam adjustment and processing position correction may be inserted during the processing.

  FIG. 4 schematically shows the surrounding cutting and the deposition film deposition state when the sample is cut out from the sample as described in FIG.

  Next, a procedure for cutting out one sample 39 from a sample will be described with reference to the flowchart of FIG. First, the orientation of the observation surface of the sample 1 is determined (S11) so that it is parallel to the vertical surface including the focused ion beam 2. If the directions are orthogonal, the stage 4 is rotated 90 degrees to the right (S12). Further, after rotating 90 °, the XYZ stage 3 is moved so that the sample enters the deflection region of the focused ion beam. When the R stage is rotated, machining position alignment (alignment) is required to determine an accurate machining position. Alignment occurs after R stage rotation. This alignment process may take several minutes. Further, the blurring in the Z direction caused by the XY movement of the stage 3 is corrected. The blur in the Z direction is detected by the Z sensor 16 that detects the Z position by applying a laser beam on the sample and receiving the reflected light. Z correction is required every time the XYZ stage 3 or the R stage 4 moves.

  Next, two markers 31 are drawn as marks on the observation surface (S13). Since these two markers are within the deflection region of the focused ion beam 2, stage movement does not occur at this time. At the same position, a protective film is generated to prevent the sample surface from being eroded by the beam. The deposition function is used to attach this film. The deposition gun 7 is normally in a retracted position so that the nozzle does not interfere with the sample, and when the deposition function is required, the tip of the nozzle is brought close to the vicinity of the beam (S14). A protective film is formed by irradiating a focused ion beam while ejecting gas from the deposition gun 7 (S15). After the film is formed by deposition, the nozzle is returned to the retracted position (S16). The depositing and unloading of the deposition gun 7 is a process included in the deposition function, and is controlled until the nozzles are loaded and unloaded by a deposition processing execution instruction. In each processing such as drawing of a marker and formation of a protective film, a beam to be used is often properly used, and switching of the beam involves switching of a mechanism such as the aperture 5.

  Next, in order to cut the transverse groove, the R stage 4 is rotated 90 ° to the left (S17). This is to make the lateral groove surface of the sample vertical. Subsequently, the large horizontal groove and the small horizontal groove are cut (S18, S19). Thereafter, the R stage 4 is rotated 90 ° to the right (S20), and the vertical groove is cut (S21). Here, it is determined whether the sample surface is an insulator or a conductor (S22). In the case of an insulator, a contact pad which is a metal deposition film for detecting that the sample is separated from the sample is formed (S23, S24, S25). The deposition film is offset so that it is also formed on the sample wall.

  Thereafter, the R stage 4 is again rotated by 90 ° (S26). The tip of the probe 9 is grounded to the contact pad surface (S27), and the probe 9 and the sample are bonded together by depositing near the grounding portion (S28, S29, S30). After bonding, the oblique grooves are cut (S31). Thus, the sample is separated from the sample, and the sample is pulled up to the retracted position together with the probe 9 (S32).

  In this state, the XYZ stage 3 is moved XY so that the cartridge 15 as a sample transfer position is positioned below the probe 9 (S33). The probe 9 with the sample is lowered to a predetermined position of the cartridge 15 (S34), and the sample is adhered by deposition (S35, S36, S37). After bonding, the tip of the probe 9 is irradiated with a beam and cut (S38). Since the tip of the probe becomes thick every time it is cut, the tip of the probe is polished by irradiating a beam (S39). Thereafter, the probe is retracted (S40).

  The above is one cycle when one sample is taken out from the sample. In the conventional method, when a plurality of samples exist on one sample, this is repeated. In one cycle, at least three R stage rotation processes and alignment processes are required. Since the stage rotation process involves not only rotation but also processes such as XY movement, alignment, and Z correction, it greatly affects the total processing time and accuracy. Therefore, it is desirable to reduce the number of treatments as much as possible.

  When cutting two or more samples from the sample, if it can be processed in the same direction, even if the XY stage is moved, it is more efficient to sequentially process the periphery of one sample. Is good. In the method of continuously processing the same direction, the amount of movement of the XY stage increases. However, in the method of sequentially processing around the sample, the R stage rotation occurs three times for each sample. If the sample moves away from the center of the R stage with this rotation, the sample position is shifted from the original position. Therefore, the XY stage must be moved back to the original position. In consideration of this alignment, Z correction, and XY stage return, a method of continuously processing portions that can be processed in the same direction is effective. Further, the processing conditions may be different even when processing is performed in the same direction. For example, the type of the beam and the processing method are different for the deposition of the protective film and the processing of the marker. Since the difference in these conditions is related to the mechanism switching, it is desirable to adopt a system in which machining under the same conditions is continuously performed so that the mechanism switching is minimized.

  Next, the algorithm of the present invention for determining the processing order will be described. The algorithm of the present invention that determines the processing order is dynamic.

  FIG. 6 is a diagram illustrating an example of a processing information table used when determining the processing order. The machining information table is a set of individual elements E1 to E9 held for each machining location. The data constituting the processing information table consists of the processing name, processing completed flag, preconditions, stage orientation when processing, stage position, beam type, processing type such as sputtering and deposition, and these data are It is held in units of one processing location. This table is used to proceed with processing from a machining location having the most suitable conditions for the current apparatus state. The “direction” described in the individual elements E1 to E9 shown in the drawing expresses from which direction in the drawing the processing should be performed in the state shown in the drawing. For example, in the state shown in the figure, the part to be processed by applying the beam from the bottom of the figure is described as “from the bottom”, and the part to be processed by applying the beam from the left side of the figure is indicated as “from the left”. Yes.

  As an example, the processing priorities are as follows: (1) Indicates that the processing execution flag is not yet executed, as viewed from the final processing state that should be called the current device state, and indicates that the processing is possible, that is, a precondition. Satisfying the highest priority, then (2) Stage orientation is the same direction (no stage rotation occurs), (3) No stage movement occurs, (4) Deposition gun control involved No (5) No beam control. The machining that matches this condition as much as possible is determined as the machining location to be processed next.

  In addition, a mechanism for dynamically changing the priority order itself was provided. In this method, the priority order of each process is described in advance in the definition table, and the process is executed from the process according to this description. For example, since the beam switching process is usually lighter in terms of mechanism control processing than the stage rotation processing, reducing the beam switching processing is not regarded as important, that is, the priority is set lower than the stage rotation processing. . Therefore, as shown in FIG. 7A, the higher order record of the priority order definition table is described in the order of stage rotation processing (without accompanying), and the lower order in the order of beam switching processing (without accompanying). In this priority definition table, for example, as shown in FIG. 7B, when the description order of the stage rotation process and the beam switching process is changed, the priority of the process is changed so that the number of beam switching is reduced as much as possible. The processing order is set. By making the processing procedure dynamic in this way, even when the number of sample acquisitions increases, the processing can proceed autonomously without describing a complicated processing procedure.

  Next, an example of processing when two samples are taken out from a sample according to the algorithm will be described. FIG. 8 is a schematic diagram showing the positional relationship between two samples on the sample 1. C1 is a vertical sample whose observation surface is parallel to the focused ion beam, and C2 is a horizontal sample whose observation surface is perpendicular to the focused ion beam. FIG. 9 shows a processing procedure for reducing the number of rotations of the R stage according to the priority table shown in FIG.

  First, the large lateral groove of C2 is sputtered (S41). Without moving the stage, the small lateral groove of C2 is processed in the same deflection region of the focused ion beam (S42). The part that can be processed at the current stage position is oblique groove processing. However, since this processing is a process of separating the probe after bonding the probe, it cannot be processed at the current timing. Since the direction of the focused ion beam is different from the original processing direction in the subsequent part, it is determined that there is no part that can be processed with this sample. Accordingly, the XY stage 3 is moved XY to the C1 sample position (S43). In the C1 processed part, the parts that can be processed in this state are two markers (S44). Further, since the protective film can be deposited, it is processed here (S45). After this, since there is no portion that can be processed in this direction, the R stage 4 is rotated 90 ° to the left (S46).

  As a result of the rotation, the stage is moved XY to a sample position close to the current beam. In this case, since C1 is closer than C2, processing of the lateral groove size of C1 is started (S47). Thereafter, the small lateral groove of C1 is processed (S48). Since there is no machining position at C1 in the current direction, the XY stage 3 is moved to C2 (S49). In C2, two markers are drawn (S50), and the protective film is deposited (S51). Further, since the lateral groove of C2 has already been processed, a vertical groove is processed (S52). Although it is more efficient to process the vertical groove before the protective deposition of C2 because it does not involve the insertion and removal of the deposition gun, if the vertical groove is carried out before the protective deposition, shavings accumulate on the sample surface and the protective deposit is deposited. The position is implemented first.

  Next, the contact pad of C2 is deposited, but the position is relatively opposite to the contact pad position of C1 (S53). This takes into account that the focused ion beam is irradiated in the current direction, that is, the sample direction as viewed from the side of the lateral groove, and the deposition film is efficiently formed on the side wall surface of the sample. After this, there is an oblique groove C1 as a place that can be processed in this state. However, since the vertical groove C1 is not processed, it is postponed. Accordingly, there is no place that can be processed in this state, and the R stage 4 is rotated 90 degrees to the right (S54).

  Since the closest processable part as viewed from directly under the current beam is the vertical groove of C1, XY movement is performed by the XY stage 3 (S55), and this is processed (S56). Next, a contact pad of C1 is formed (S57). Since there is no portion that can be processed without rotating the stage in C1, the stage is moved to the vicinity of C2 (S58), and the probe 9 is deposited and bonded to the contact pad (S59). After bonding, the sample is separated from the sample 1 by processing the oblique groove of C2. Thereafter, the probe 9 is pulled up, and the XY stage 3 is moved to the cartridge 15. The probe 9 is lowered to the bonding position of the cartridge, and bonded by deposition when the sample and the cartridge contact each other. After the deposition is completed, the probe 9 is cut off with the focused ion beam (S60).

  After pulling up the probe 9 to the retracted position, the R stage 4 is rotated 90 ° counterclockwise to take out the C1 sample (S61), and the XY stage 3 is moved to the vicinity of C1 (S62). The probe 9 is lowered to the contact pad position of C1, and the sample is adhered by deposition (S63). After bonding, the oblique groove of C1 is cut, and the sample is separated from the sample. Thereafter, stage movement, probe operation, and deposition control are performed in the same manner as the method of attaching the C2 sample to the cartridge (S64).

  The feature of this process is that the current stage position and orientation and the sampling process are taken into consideration, and two samples can be acquired by three stage rotations. This method can also be applied when the number of samples collected from one sample is three or more.

  Conventionally, when there are multiple places to be processed by a FIB processing device on one sample, the processing has been performed in the order described in the recipe created by the operator, so there is a wasteful movement in terms of device control. There are problems such as that it takes a long time and hardware mechanism switching frequently occurs and the machining accuracy is lowered. According to the method of the present invention, the useless movement of these apparatuses and the number of switching mechanisms can be reduced, and the total machining time can be shortened and the machining accuracy can be improved. For example, looking at the number of R stage rotation processes, three times are required to acquire one sample from the sample, and 3 n R stage rotation processes are required when n samples are taken out in the conventional method. On the other hand, in this method, even if the number of samples n increases, the number of rotations of the R stage is only three. Since the alignment process accompanying the rotation may take several minutes, the total processing time is significantly reduced according to the method of the present invention when a plurality of samples are acquired.

  Next, another example of the algorithm for determining the processing order will be described. The example described here is a method that considers the time factor in weighting. According to this method, priority is given to beam switching when the stage movement distance is large, or priority is given to stage movement when the aperture switching distance is long. It becomes possible to do.

  FIG. 10 is an explanatory diagram showing a method of assigning coefficients to elements related to mechanism control among elements described in the machining information table and comparing the total cost to determine the next machining. In the illustrated example, as shown in the conversion coefficient table F2, 50 points for stage rotation per unit (90 °), 1 point for stage movement per unit distance, 6 points for beam switching to adjacent aperture, machining position 18 points are allocated to the movement of the deposition gun to or from the machining position, and the total points of mechanism control necessary to move from the current state F1 to each machining location are calculated as the total cost. Compare. In the illustrated example, since the difference between the current state F1 and the candidate groups F3, F4, and F5 is quantified, the machining name “1 protected deposition” (F3) is the lowest cost at the total cost “54”. This is the next processing.

  The conversion coefficient table F2 shown in FIG. 10 is calculated based on the time when the device mechanism actually operates. Specifically, a command for operating the apparatus is input from the information input apparatus 11, and the time until the apparatus returns a completion response is measured. This time is converted into a unit of each control mechanism. For example, the stage is stored in the storage device 12 as a movement amount (speed) per unit time. In this method, the latest data can be used for the next route derivation every time the apparatus operates. Separately from this, device spec data before executing the recipe is provided, and a device for switching between the two is used. The time required for stage movement and beam switching differs depending on the amount of movement. On the other hand, changing the direction and taking in and out the deposition gun do not take a linear value, and therefore hold them for a total time.

  Due to the mechanism of the apparatus, one of the systems that can be controlled simultaneously may be substantially hidden in the control time of the other depending on the combination. For systems that can be processed in parallel, the combinations are tabulated, and the control time of the system that is effectively hidden is treated as 0, so that the total cost can be lowered and the priority can be raised.

  FIG. 11 is a diagram for explaining a processing example of the state monitoring program installed in the computer 10. The state monitoring program includes a process 41 for acquiring the current apparatus state and a process 42 for collecting a distance and time when a mechanism such as a device stage and an aperture operates and updating the mechanism operation database 43. The former obtains the type of processing such as stage orientation, stage position, beam type and sputtering or deposition. This acquired data is used for deriving an appropriate processing point to be processed next in the recipe execution program. The latter obtains the stage moving speed, aperture switching speed, deposition gun loading / unloading speed, alignment time, Z correction time, and the like from the apparatus. These pieces of information are overwritten as the latest data in the mechanism operation database 43 at the acquired timing. In addition, as the mechanism operation database, a default mechanism operation database holding a preset default value is prepared separately, and it is possible to select which one is used to execute the recipe according to an operator instruction.

  FIG. 12 is a flowchart illustrating a processing example of the recipe execution program. When executing the recipe, the operator selects an execution method on the recipe execution operation screen 20 shown in FIG. 2 (S71). The batch method is a method in which a sequence of all processes is set in advance before executing the recipe, and the sequential method is a method for determining the next processing place when the processing of one place is completed. After determining the execution method, the designated recipe is divided into minimum processing units (S72). Next, a machining information table is created with the divided minimum machining units (S73). Next, the process proceeds to the optimum candidate selection process (S74). The optimum candidate selection process (S74) is a process for finding an appropriate machining location, and the most suitable machining location from the machining information table on the basis of the current apparatus state 90 and information in the mechanism operation database 91 designated from the recipe execution operation screen in advance. Is derived. The execution method is determined (S75), and when the designated execution method is the sequential method, machining of the derived appropriate machining location is executed (S76). On the other hand, in the case of the batch method, the derived machining information of the optimum machining location is sequentially held in the processing order table (S77).

  In the case of passing through step 76, the current machining information table content becomes the current apparatus state. If the process goes through step 77, it is assumed that the processing part has been processed, and the contents of the processing information table are set to the current apparatus state (S78). In either method, since the current machining location is already processed and not set as the next processing candidate, the execution flag is set to ON (S79), and the next appropriate candidate is selected (S74). In this way, the processing from step 74 to step 80 is repeated until there is no processing candidate.

  Next, the execution mode is determined (S81), and when the execution mode is the sequential method, the process ends when there are no processing candidates. When the execution mode is the batch method, the processing is continuously executed according to the order stored in the processing order table (S82). If it is necessary to perform an exceptional process such as adjustment of the focused ion beam during the sequential processing, the operator presses the “Pause” button on the recipe execution operation screen 20 in FIG. Then, the processing according to the recipe is temporarily interrupted after the execution of the single processing in step 76. For example, the operator manually moves the stage to bring the beam away from the sample, and performs beam adjustment there. Thereafter, when the “Continue” button is pressed, in the process of step 78, the current apparatus state is taken in instead of the contents of the machining information table of the immediately preceding machining location, and the process returns to the machining process according to the recipe. For this reason, in the optimum candidate selection immediately after the interruption of the recipe (S74), an optimum processing candidate is selected by searching from the apparatus state after the exception process is performed.

DESCRIPTION OF SYMBOLS 1 ... Sample to be processed, 2 ... Focused ion beam, 3 ... XYZ triaxial stage, 4 ... R stage, 5 ... Aperture, 6 ... Focused ion beam optical system, 7 ... Gas ejection nozzle, 8 ... Detector, 9 ... Sampling Probe: 10: Computer, 11: Information input device, 12: Storage device, 13: Display device, 14: Beam deflection control device, 15: Cartridge, 16 ... Z sensor, 20 ... Recipe execution operation screen, 31 ... Marker, 32 Protective film 33 Large horizontal groove 34 Small horizontal groove 35 Vertical groove 36 Contact pad 37 Oblique groove 38 Observation position 39 Sample C1 Vertical sample C2 Horizontal sample

Claims (2)

A stage on which a sample can be placed;
A focused ion beam optical system for processing the sample by irradiating the sample with a focused ion beam from an oblique direction;
A computer for processing and controlling the recipe;
An information input device for setting at least processing,
In a sample processing apparatus having at least a display device that displays a sample image by the focused ion beam,
The display device includes a menu button to select one of the processing method in the method for determining the next machining spot when the scheme previously Crossed sequence of all machining locations before executing the recipe, the processing of one place finished A sample processing apparatus, characterized by displaying a screen on which is arranged. A stage on which a sample can be placed;
A focused ion beam optical system for processing the sample by irradiating the sample with a focused ion beam from an oblique direction;
A computer for processing and controlling the recipe;
An information input device for setting at least processing,
In a sample processing apparatus having at least a display device that displays a sample image by the focused ion beam,
The display device executes the recipe using a database in which the operation of the mechanism included in the sample processing apparatus is defined in advance, or executes the recipe using a database reflecting a result of operating the sample processing apparatus. A sample processing apparatus that displays a screen on which a menu button for selecting is displayed .

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