Detection method for diaphragm positioning precision of electron beam detection equipment and related product

Abstract

The invention relates to a detection method for diaphragm positioning precision of electron beam detection equipment and a related product. The detection method comprises the following steps: acquiring a reference image and a reference centering coordinate of a diaphragm; the reference centering coordinate is a position coordinate of the diaphragm under the condition that the diaphragm and an electron optical system of the electron beam detection equipment are centered, and the reference image is a back scattering electron image obtained under the condition that the diaphragm and the electron optical system are centered; repeatedly executing the moving alignment process of the diaphragm to obtain a plurality of actually measured centering coordinates; the moving alignment process is configured as follows: the diaphragm is moved from a preset initial coordinate to a concentric position of the backscattered electron image and the reference image, and the actually measured centering coordinate is the coordinate of the diaphragm after moving alignment; and obtaining the positioning precision of the diaphragm according to the plurality of actual measurement centering coordinates and the reference centering coordinates. According to the scheme, the positioning precision of the diaphragm of the electron beam detection equipment can be quantitatively obtained, so that a basis is provided for judging whether the electron beam detection equipment meets the detection precision requirement or not.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor detection technology, and in particular to a detection method for aperture positioning accuracy of electron beam detection equipment, a computer-readable storage medium, a computer program product and a computer device. Background Art

[0002] In recent years, with the rapid development of the semiconductor industry, the process technology of electron beam inspection equipment used in defect detection in wafer manufacturing has become more and more perfect. Among them, the number of apertures with different apertures used in electron beam inspection equipment has increased. In order to ensure that apertures with different apertures can be quickly switched, a mechanical structure is set in the relevant technology to control the movement of the aperture.

[0003] However, when the mechanical structure moves, there will be a certain position deviation, which will cause positioning deviation when the aperture is switched. The electron beam detection equipment has high requirements for the positioning accuracy of the aperture. When the positioning accuracy of the aperture is poor, it will seriously affect the stability and reliability of the measurement results of the electron beam detection equipment. Summary of the invention

[0004] In view of the above problems, the present invention is proposed to provide a method for detecting aperture positioning accuracy for an electron beam detection device, a computer-readable storage medium, a computer program product and a computer device that overcome the above problems or at least partially solve the above problems.

[0005] An object of the present invention is to provide a method for detecting aperture positioning accuracy, which can quantitatively detect the aperture positioning accuracy of an electron beam detection device, thereby providing a basis for determining whether the electron beam detection device meets the detection accuracy requirements.

[0006] Specifically, according to one aspect of the present invention, the present invention provides a method for detecting the aperture positioning accuracy of an electron beam detection device, which comprises:

[0007] S1, acquiring a reference image and reference centering coordinates of the aperture; the reference centering coordinates are position coordinates of the aperture when the aperture is centered with the electron optical system of the electron beam detection device, and the reference image is a backscattered electron image obtained when the aperture is centered with the electron optical system;

[0008] S2, repeatedly executing the movement alignment process of the aperture to obtain a plurality of measured centering coordinates; the movement alignment process is configured to: move the aperture from a preset initial coordinate to a position where the backscattered electron image and the reference image are concentric, and the measured centering coordinates are the coordinates of the aperture after movement alignment;

[0009] S3, obtaining the positioning accuracy of the aperture according to the multiple measured centering coordinates and the reference centering coordinates.

[0010] Optionally, the steps of the mobile alignment process include:

[0011] Controlling the aperture to perform initial adjustment movement from the initial coordinate to the reference centering coordinate;

[0012] Focusing the electron beam of the electron beam detection device on the aperture, and making the electron beam scan the aperture in a range equal to or larger than the aperture of the aperture, to obtain the backscattered electron image;

[0013] determining whether the backscattered electron image is concentric with the reference image;

[0014] If they are not concentric, the aperture is controlled to perform one or more polyphonic movements until the backscattered electron image is concentric with the reference image.

[0015] Optionally, the step of controlling the aperture to perform an initial adjustment movement from the initial coordinate to the reference centering coordinate comprises:

[0016] The distance between the reference centering coordinate and the initial coordinate is taken as the target distance, and distance feedback adjustment is performed.

[0017] Optionally, the step of controlling the aperture to perform an initial adjustment movement from the initial coordinate to the reference centering coordinate comprises:

[0018] The reference centering coordinate is used as the target coordinate to perform coordinate feedback adjustment.

[0019] Optionally, in step S2, the method for determining whether the backscattered electron image and the reference image are concentric includes:

[0020] Acquiring the contour of the backscattered electron image and the contour of the reference image;

[0021] adjusting the magnification of the backscattered electron image so that the area of ​​the region within the outline of the backscattered electron image is equal to the area of ​​the region within the outline of the reference image;

[0022] In response to the edge of the contour of the backscattered electron image coinciding with the edge of the contour of the reference image, it is determined that the backscattered electron image and the reference image are concentric.

[0023] Optionally, in step S2, the method for determining whether the backscattered electron image and the reference image are concentric includes:

[0024] Using a preset image algorithm, obtaining the center of the backscattered electron image and the center of the reference image;

[0025] In response to the center of the backscattered electron image being aligned with the center of the reference image, it is determined that the backscattered electron image and the reference image are concentric.

[0026] Optionally, the S3 step includes:

[0027] Determine the one of the multiple measured centering coordinates that is farthest from the reference centering coordinate, and record it as the farthest measured coordinate;

[0028] The positioning accuracy is obtained according to the distance between the farthest measured coordinate and the reference centering coordinate.

[0029] Optionally, the electron beam detection device drives the aperture to move in the X-axis direction through a first driving mechanism, and drives the aperture to move in the Y-axis direction through a second driving mechanism; the step S3 includes:

[0030] Determine the deviation value of the X-coordinate value of the reference centering coordinate that is the largest among the X-coordinate values ​​of the multiple measured centering coordinates as the linear positioning accuracy of the aperture in the X-axis direction;

[0031] The deviation value of the Y coordinate value of the plurality of measured centering coordinates which deviates the most from the Y coordinate value of the reference centering coordinate is determined as the linear positioning accuracy of the aperture in the Y-axis direction.

[0032] Optionally, the electron beam detection device has a plurality of apertures arranged at intervals, each of the apertures corresponding to one of the reference centering coordinates;

[0033] In the step S2, the distance between the initial coordinate and the reference centering coordinate of the aperture to be detected is greater than or equal to the minimum distance between any two of the plurality of apertures.

[0034] According to another aspect of the present invention, there is also provided a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned method for detecting the aperture positioning accuracy are implemented.

[0035] According to yet another aspect of the present invention, there is also provided a computer program product, comprising a computer program, which implements the steps of the above-mentioned method for detecting aperture positioning accuracy when executed by a processor.

[0036] According to yet another aspect of the present invention, there is provided a computer device comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-mentioned method for detecting aperture positioning accuracy.

[0037] In the detection method of aperture positioning accuracy of the present invention, the reference image can accurately reflect the position of the aperture when the aperture is centered with the electron optical system, and the backscattered electron image can accurately reflect the current position of the aperture. The reference centering coordinates are the reference coordinates in the aperture control system when the aperture is centered with the electron optical system, and the measured centering coordinates are the actual coordinates in the aperture control system when the aperture is centered with the electron optical system. By repeatedly executing the mobile alignment process to obtain multiple measured centering coordinates, and comparing them with the reference centering coordinates, the positioning accuracy of the aperture of the electron beam detection device is quantitatively obtained, thereby providing a basis for judging whether the electron beam detection device meets the detection accuracy requirements.

[0038] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0040] Figure 1 is a schematic flow chart of a detection method according to an embodiment of the present invention;

[0041] Figure 2 is a schematic flow chart of a mobile alignment process of a detection method according to an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of a flow chart of determining the concentricity of a backscattered electron image and a reference image according to a detection method of an embodiment of the present invention;

[0043] Figure 4 is a schematic diagram of a flow chart of determining the concentricity of a backscattered electron image and a reference image according to a detection method of another embodiment of the present invention;

[0044] Figure 5 is a schematic diagram of a flow chart of obtaining positioning accuracy according to a detection method according to an embodiment of the present invention;

[0045] Figure 6 is a schematic diagram of a flow chart of obtaining positioning accuracy of a detection method according to another embodiment of the present invention;

[0046] Figure 7 is a schematic structural diagram of an electron beam detection device according to a detection method of one embodiment of the present invention;

[0047] Figure 8 is a schematic diagram of a backscattered electron image and a reference image of a detection method according to an embodiment of the present invention;

[0048] Fig. 9 is a schematic diagram of a computer program product according to an embodiment of the present invention;

[0049] Fig.10 is a schematic diagram of a computer-readable storage medium according to an embodiment of the present invention; and

[0050] Fig.11 is a schematic diagram of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0051] The purpose of the method for detecting the aperture positioning accuracy of the electron beam detection device in this embodiment is to quantitatively detect the aperture positioning accuracy of the electron beam detection device, thereby providing a reference for determining whether the electron beam detection device meets the use requirements.

[0052] Figure 1 FIG. 1 is a flow chart of a detection method according to an embodiment of the present invention. The method may generally include:

[0053] S1, obtaining a reference image and reference centering coordinates of the aperture. The reference centering coordinates are the position coordinates of the aperture when the aperture is centered with the electron optical system of the electron beam detection device, and the reference image is a backscattered electron image obtained when the aperture is centered with the electron optical system.

[0054] S2, repeatedly executing the movement alignment process of the aperture to obtain a plurality of measured centering coordinates. The movement alignment process is configured to: move the aperture from the preset initial coordinates to a position where the backscattered electron image and the reference image are concentric, and the measured centering coordinates are the coordinates of the aperture after movement alignment.

[0055] S3, obtaining the positioning accuracy of the aperture according to the plurality of measured centering coordinates and the reference centering coordinates.

[0056] Electron beam detection equipment usually generates detection images based on electron beams for microscopic detection, and may include scanning electron microscopes (SEM), transmission electron microscopes (TEM), etc. The following takes a scanning electron microscope as an example to illustrate the technical solution of the embodiment of the present invention. Figure 7The scanning electron microscope generally includes an electron beam source 41, a focusing coil 42 (Condenser Lens, referred to as CL), an astigmatism correction device 43 (Stigmator), an adjustable aperture bar, a detector 45, and a sample stage 46. A plurality of apertures 44 with the same or different apertures can be arranged at intervals on the adjustable aperture bar. The focusing coil 42 can focus the electron beam 51 near the aperture 44. The astigmatism correction device 43 can drive the electron beam 51 to scan.

[0057] The aperture bar can be moved under the drive of the mechanical structure, so as to adjust and switch the aperture position. Generally, the aperture is adjusted on a plane perpendicular to the central axis of the aperture, and the central axis of the aperture is usually parallel to the main axis of the electron optical system of the scanning electron microscope. By adjusting the aperture bar in two dimensions in a plane perpendicular to the main axis of the electron optical system, the aperture of a specific aperture is aligned with the center of the electron beam to allow electrons in the center of the electron beam to pass through and block electrons that deviate from the center.

[0058] When the electron beam passes through the aperture and hits the sample on the sample stage or the loading surface of the sample stage, it will form backscattered electrons, and a backscattered electron image (by Figure 7 The backscattered electron beam 52 is generated after hitting the detector 45). The backscattered electron image is usually presented on the display screen of the scanning electron microscope. The loading surface of the sample stage is usually flat and perpendicular to the main axis of the electron optical system. When the loading surface is smooth enough, the loading surface can form enough backscattered electrons and form a light spot of the backscattered electron image with a contour corresponding to the aperture shape and position of the aperture. The aperture is usually circular, and the contour of the backscattered electron image is a circular spot, so it is also easier to obtain the center of the backscattered electron image. In some optional embodiments, a preset sample can be placed on the sample stage, and the preset sample has a stronger ability to scatter electrons (for example, the atomic number of the material is larger), so that a backscattered electron image with a higher contrast is formed through the detector, so as to accurately determine the center and / or edge of the contour of the backscattered electron image. In some optional embodiments, a specific pattern can be set on the loading surface or the preset sample surface, such as a cross-shaped concave-convex pattern, a dot pattern, etc. in the center, to form a recognizable image feature in the backscattered electron image, so as to further improve the speed and accuracy of determining the center and / or contour edge of the backscattered electron image.

[0059] The reference centering coordinates are the reference coordinates in the aperture control system when the aperture is centered with the electronic optical system, and the measured centering coordinates are the actual coordinates in the aperture control system when the aperture is centered with the electronic optical system. It should be understood that the coordinates of the aperture in this embodiment are the coordinates mapped in the aperture control system. Taking the aperture as an example of position adjustment by a servo motor, the current coordinates of the aperture are the current position of the motor recorded in the servo motor control system, which is usually fed back to the control system in real time through feedback devices such as encoders. Exemplarily, the current coordinates are represented by the number of pulses of the motor, which can tell the control system the current position of the motor. The reference centering coordinates can be represented by the number of pulses that should theoretically (or after calibration) correspond to when the aperture is centered with the electronic optical system, and the measured centering coordinates can be represented by the actual number of pulses when the aperture is centered with the electronic optical system.

[0060] In this embodiment, the reference image can be a measured image of the backscattered electron image, or an abstract image including relevant features of the measured image. For example, the reference image can be a backscattered electron image with a circular spot, and the center of the circular spot corresponds to the main axis of the electron optical system. For example, the reference image can be a circle, a circle plus a cross axis, or multiple concentric circles. The reference image can be directly presented on the display screen of the scanning electron microscope, or it can not be presented on the display screen. Please refer to Figure 8 , the figure illustrates a partial image presented on a display screen of an embodiment, wherein the white circular light spot is a backscattered electron image 61 and the blue circle is a reference image 62.

[0061] In this embodiment, the initial coordinates may be random positions or preset positions, and there is no limitation here. Due to mechanical or control deviations, the coordinate values ​​recorded by the aperture control system may deviate from the actual values, and / or the movement distance recorded by the aperture control system may deviate from the actual values. Therefore, in each round of the movement alignment process, when the aperture moves from the initial coordinates to a position where the center of the backscattered electron image is aligned with the center of the reference image, the measured centering coordinates may be equal or unequal. The difference between each measured centering coordinate and the reference centering coordinate can be used to quantitatively obtain the aperture positioning accuracy of the electron beam detection device, thereby providing a basis for determining whether the electron beam detection device meets the use requirements.

[0062] It should be noted that the more rounds of the mobile alignment process are repeated in step S2, the more measured centering coordinates are obtained, and the final positioning accuracy can more truly reflect the aperture positioning accuracy of the electron beam detection device. In actual use, the number of rounds of the mobile alignment process can be selected according to needs.

[0063] In some embodiments of the detection method of the present invention, Figure 2 As shown, the steps of the mobile alignment process include:

[0064] S211, controlling the aperture to perform initial adjustment movement from the initial coordinates to the reference centering coordinates.

[0065] S213, focusing the electron beam of the electron beam detection device on the diaphragm, and making the electron beam scan the diaphragm in a range equal to or larger than the aperture of the diaphragm to obtain a backscattered electron image.

[0066] S215, determining whether the backscattered electron image is concentric with the reference image.

[0067] S217, if they are not concentric, control the aperture to perform one or more polyphonic movements until the backscattered electron image and the reference image are concentric.

[0068] The initial coordinates may be random coordinates or preset coordinates. For example, the coordinates in the aperture control system may be set to preset coordinates when the number of pulses of the aperture motor is reset to zero. In this embodiment, the initial adjustment movement is used to simulate the movement process of the aperture during actual operation. On the one hand, the positioning accuracy obtained by the detection truly reflects the positioning performance of the aperture. On the other hand, at the initial coordinates, the aperture to be detected may be far away from the center of the electron optical system, and may not generate a corresponding backscattered electron image, or the generated backscattered electron image may be of poor quality. Only when the aperture is near the center position can a high-quality backscattered electron image be obtained.

[0069] In this embodiment, the electron beam is controlled to focus on the aperture by the focusing coil, and the electron beam is controlled to scan the aperture in a range equal to or larger than the aperture by the astigmatism correction device. When the electron beam scans the aperture in a range equal to or larger than the aperture, the contour of the backscattered electron image will be able to correctly reflect the shape of the aperture, and the center of the backscattered electron image will be able to correctly reflect the position of the central axis of the aperture. When the electron beam scans the aperture in a range smaller than the aperture, the backscattered electron image cannot correctly reflect the shape of the aperture and the position of the central axis of the aperture.

[0070] The polyphonic movement is usually a fine adjustment to make the backscattered electron image and the reference image concentric. In actual use, the distance of each polyphonic movement is usually a few microns.

[0071] In some embodiments of the detection method of the present invention, the step of controlling the aperture to perform an initial adjustment movement from the initial coordinate to the reference centering coordinate includes:

[0072] The distance between the reference centering coordinate and the initial coordinate is taken as the target distance, and distance feedback adjustment is performed.

[0073] In this embodiment, the aperture control system may use an incremental encoder to reflect the target distance through the increment of the number of pulses, thereby performing distance feedback adjustment, so that the aperture stops after changing the number of pulses corresponding to the target distance. It should be noted that the distance between the reference centering coordinate and the initial coordinate may be a vector distance, which includes both the length of the distance and the direction of the distance.

[0074] In some embodiments of the detection method of the present invention, the step of controlling the aperture to perform an initial adjustment movement from the initial coordinate to the reference centering coordinate includes:

[0075] The reference centering coordinate is used as the target coordinate to perform coordinate feedback adjustment.

[0076] In this embodiment, the aperture control system may use an absolute encoder to reflect the coordinates through the absolute pulse number, thereby performing coordinate feedback adjustment so that the aperture stops at the absolute pulse number corresponding to the target coordinates.

[0077] In some embodiments of the detection method of the present invention, Figure 3 As shown, in step S2, the method for determining the concentricity of the backscattered electron image and the reference image includes:

[0078] S221, acquiring the contour of the backscattered electron image and the contour of the reference image.

[0079] S223, adjusting the magnification of the backscattered electron image so that the area of ​​the region within the contour of the backscattered electron image is equal to the area of ​​the region within the contour of the reference image.

[0080] S225 , in response to the edge of the contour of the backscattered electron image coinciding with the edge of the contour of the reference image, determining that the backscattered electron image and the reference image are concentric.

[0081] The following description is made by taking the case where the outline of the backscattered electron image is a circular spot and the outline of the reference image is a circle as an example. In this embodiment, the magnification of the backscattered electron image can be adjusted by the zoom function of the display screen to change the size of the area within its outline (it can also be the size of the diameter of the outline). During the zooming process of the backscattered electron image, its center position will not change. Since the edge of the outline of the backscattered electron image directly reflects the shape and position of the aperture of the diaphragm, when the edge of the outline of the backscattered electron image coincides with the edge of the outline of the reference image, it indicates that the center of the backscattered electron image and the center of the reference image are aligned. This alignment method is easy to control and has high accuracy.

[0082] In actual use, the steps of adjusting the magnification of the backscattered electron image and moving the aperture position can be performed sequentially, simultaneously, or even crosswise. For example, the magnification of the backscattered electron image can be adjusted multiple times, and the aperture position can be moved multiple times.

[0083] In some embodiments of the detection method of the present invention, Figure 4 As shown, in step S2, the method for determining the concentricity of the backscattered electron image and the reference image includes:

[0084] S231, using a preset image algorithm, obtaining the center of the backscattered electron image and obtaining the center of the reference image.

[0085] S233: In response to the center of the backscattered electron image being aligned with the center of the reference image, it is determined that the backscattered electron image and the reference image are concentric.

[0086] The center of the backscattered electron image can be quickly calculated by a preset image algorithm. In this embodiment, the center of the reference image (for example, the position of the center of the reference image on the display screen) can be directly obtained, or the center of the reference image can be calculated by a preset image algorithm. Compared with the previous embodiment, the method of this embodiment omits the step of adjusting the magnification of the backscattered electron image, which can improve the efficiency of detection.

[0087] In some embodiments of the detection method of the present invention, Figure 5 As shown, step S3 includes:

[0088] S311, determine the one of the multiple measured centering coordinates that is farthest from the reference centering coordinate and record it as the farthest measured coordinate.

[0089] S313, obtaining the positioning accuracy according to the distance between the farthest measured coordinate and the reference centering coordinate.

[0090] This embodiment is applicable to the case where the number of rounds of the mobile alignment process is sufficient. By calculating the positioning accuracy based on the distance between the farthest measured coordinate and the reference centering coordinate, the worst positioning performance of the aperture can be quantitatively reflected to a certain extent, thereby providing a basis for judging whether the electron beam detection device meets the detection accuracy requirements.

[0091] In some embodiments of the detection method of the present invention, Figure 6 As shown, the electron beam detection device drives the aperture to move in the X-axis direction through the first driving mechanism, and drives the aperture to move in the Y-axis direction through the second driving mechanism. Step S3 includes:

[0092] S321, determining the deviation value of the X-coordinate value of the reference centering coordinate that deviates the most from the X-coordinate value of the multiple measured centering coordinates as the linear positioning accuracy of the aperture in the X-axis direction.

[0093] S323, determining the deviation value of the Y coordinate value of the reference centering coordinate that deviates the most from the Y coordinate value of the multiple measured centering coordinates as the linear positioning accuracy of the aperture in the Y-axis direction.

[0094] In this embodiment, the X-axis and the Y-axis are orthogonal, and the XY plane may be perpendicular to the main axis of the electron optical system, that is, perpendicular to the central axis of the aperture. Exemplarily, the first driving mechanism may be a first linear motor, and the second driving mechanism may be a second linear motor. The first linear motor may be provided with a first encoder correspondingly, so that the X coordinate value of the aperture is represented by the number of pulses of the first encoder. The second linear motor may be provided with a second encoder correspondingly, so that the Y coordinate value of the aperture is represented by the number of pulses of the second encoder.

[0095] In this embodiment, by respectively obtaining the linear positioning accuracy in the X-axis direction and the Y-axis direction, the two driving mechanisms for adjusting the aperture position can be judged independently, so as to determine which driving mechanism meets the positioning accuracy requirement and which driving mechanism does not meet the positioning accuracy requirement, thereby providing a reference for improving the driving mechanism of the aperture.

[0096] In some embodiments of the detection method of the present invention, the electron beam detection device has a plurality of apertures arranged at intervals, and each aperture corresponds to a reference centering coordinate.

[0097] In step S2, the distance between the initial coordinates and the reference centering coordinates of the aperture to be detected is greater than or equal to the minimum distance between any two of the plurality of apertures.

[0098] In actual use, when switching between two specific apertures, the distance between the two apertures is the moving distance of the aperture. If the distance between the measured centering coordinates and the initial coordinates is shorter, the moving distance of the aperture between the two is shorter, which is not conducive to accurately obtaining the positioning accuracy of the aperture in actual use.

[0099] In some optional embodiments, the distance between the initial coordinate and the reference centering coordinate of the aperture to be detected in the X-axis direction is greater than or equal to the minimum distance threshold of the X-axis, and the distance in the Y-axis direction is greater than or equal to the minimum distance threshold of the Y-axis. In this way, the measured positioning accuracy can accurately reflect the linear positioning accuracy in both the X-axis direction and the Y-axis direction.

[0100] It should be understood that the reference image is the backscattered electron image corresponding to the alignment of the aperture and the electron optical system. Therefore, in the mobile alignment process step, the reference image is applicable to any aperture. For apertures with different apertures, it is only necessary to adjust the magnification of their backscattered electron images.

[0101] The flowchart provided by the embodiment of the present invention is not intended to indicate that the operations of the method will be performed in any particular order, or that all operations of the method are included in all every case. In addition, the method may include additional operations. Within the scope of the technical ideas provided by the embodiment of the present invention method, additional changes may be made to the above method.

[0102] It should be understood that in some embodiments, each part can be implemented by hardware, software, firmware or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system.

[0103] The embodiment of the present invention further provides a computer program product 10 , a computer readable storage medium 20 , and a computer device 30 . Fig. 9 is a schematic diagram of a computer program product 10 according to an embodiment of the present invention, Fig.10 is a schematic diagram of a computer-readable storage medium 20 according to an embodiment of the present invention, Fig.11 is a schematic diagram of a computer device 30 according to an embodiment of the present invention. The computer program product 10 includes a computer program 11, which implements the steps of any of the above detection methods when executed by a processor 32. The computer readable storage medium 20 stores the above computer program 11, which implements the steps of any of the above detection methods when executed by the processor 32. The computer device 30 may include a memory 31, a processor 32, and the computer program 11 stored in the memory 31 and running on the processor 32.

[0104] The computer program 11 for performing the operation of the present invention may be an assembly instruction, an instruction set architecture (ISA) instruction, a machine instruction, a machine-related instruction, a microcode, a firmware instruction, a state setting data, a configuration data of an integrated circuit, or a source code or an object code written in any combination of one or more programming languages ​​and process programming languages. The computer program 11 may be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer via any type of network (including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider via the Internet). In some embodiments, in order to perform various aspects of the present invention, an electronic circuit including, for example, a programmable logic circuit, a field programmable gate array (FPGA) or a programmable logic array (PLA) may execute computer-readable program instructions by utilizing the state information of the computer-readable program instructions to personalize the electronic circuit.

[0105] In the description of this embodiment, the computer program product 10 is a related product including the computer program 11 .

[0106] For the purpose of the description of the present embodiment, the computer readable storage medium 20 is a tangible device capable of retaining and storing the computer program 11, which can be any device that can contain, store, communicate, propagate or transmit the computer program 11 for use with an instruction execution system, device or apparatus or in conjunction with these instruction execution systems, devices or apparatuses. More specific examples (a non-exhaustive list) of the computer readable storage medium 20 include the following: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, and any suitable combination of the above.

[0107] The computer device 30 may be, for example, a server, a desktop computer, a notebook computer, a tablet computer, or a smart phone. In some examples, the computer device 30 may be a cloud computing node. The computer device 30 may be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. Typically, a program module may include routines, programs, target programs, components, logic, data structures, etc. that perform specific tasks or implement specific abstract data types. The computer device 30 may be implemented in a distributed cloud computing environment where remote processing devices linked via a communication network perform tasks. In a distributed cloud computing environment, program modules may be located on a local or remote computing system storage medium including a storage device.

[0108] The computer device 30 may include a processor 32 adapted to execute stored instructions, and a memory 31 providing temporary storage space for the operation of the instructions during operation. The processor 32 may be a single-core processor, a multi-core processor, a computing cluster, or any number of other configurations. The memory 31 may include a random access memory (RAM), a read-only memory, a flash memory, or any other suitable storage system.

[0109] The computer device 30 may also include a network adapter / interface and an input / output (I / O) interface. The I / O interface allows data to be input and output with external devices that may be connected to the computer device. The network adapter / interface may provide communication between the computer device and a network, which is typically shown as a communication network.

[0110] At this point, those skilled in the art should recognize that, although multiple exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived based on the content disclosed in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all these other variations or modifications.

Claims

1. A method for detecting the aperture positioning accuracy of an electron beam detection device, characterized in that: include: S1, acquiring a reference image and a reference centering coordinate of the aperture; The reference centering coordinates are the position coordinates of the aperture when the aperture is centered with the electron optical system of the electron beam detection device, and the reference image is a backscattered electron image obtained when the aperture is centered with the electron optical system; S2, repeatedly executing the movement alignment process of the aperture to obtain a plurality of measured centering coordinates; the movement alignment process is configured to: move the aperture from a preset initial coordinate to a position where the backscattered electron image and the reference image are concentric, and the measured centering coordinates are the coordinates of the aperture after movement alignment; S3, obtaining the positioning accuracy of the aperture according to the multiple measured centering coordinates and the reference centering coordinates.

2. The detection method according to claim 1, characterized in that: The steps of the mobile alignment process include: Controlling the aperture to perform initial adjustment movement from the initial coordinate to the reference centering coordinate; Focusing the electron beam of the electron beam detection device on the aperture, and making the electron beam scan the aperture in a range equal to or larger than the aperture of the aperture, to obtain the backscattered electron image; determining whether the backscattered electron image is concentric with the reference image; If they are not concentric, the aperture is controlled to perform one or more polyphonic movements until the backscattered electron image is concentric with the reference image.

3. The detection method according to claim 2, characterized in that: The step of controlling the aperture to perform initial adjustment movement from the initial coordinate to the reference centering coordinate comprises: Taking the distance between the reference centering coordinate and the initial coordinate as the target distance, performing distance feedback adjustment; or The reference centering coordinate is used as the target coordinate to perform coordinate feedback adjustment.

4. The detection method according to claim 1, characterized in that: In the step S2, the method for determining that the backscattered electron image is concentric with the reference image includes: Acquiring the contour of the backscattered electron image and the contour of the reference image; adjusting the magnification of the backscattered electron image so that the area of ​​the region within the outline of the backscattered electron image is equal to the area of ​​the region within the outline of the reference image; In response to the edge of the contour of the backscattered electron image coinciding with the edge of the contour of the reference image, it is determined that the backscattered electron image and the reference image are concentric.

5. The detection method according to claim 1, characterized in that: In the step S2, the method for determining that the backscattered electron image is concentric with the reference image includes: Using a preset image algorithm, obtaining the center of the backscattered electron image and the center of the reference image; In response to the center of the backscattered electron image being aligned with the center of the reference image, it is determined that the backscattered electron image and the reference image are concentric.

6. The detection method according to claim 1, characterized in that: The S3 step includes: Determine the one of the multiple measured centering coordinates that is farthest from the reference centering coordinate, and record it as the farthest measured coordinate; The positioning accuracy is obtained according to the distance between the farthest measured coordinate and the reference centering coordinate.

7. The detection method according to claim 1, characterized in that: The electron beam detection device drives the aperture to move in the X-axis direction through a first driving mechanism, and drives the aperture to move in the Y-axis direction through a second driving mechanism; the S3 step includes: Determine the deviation value of the X-coordinate value of the reference centering coordinate that is the largest among the X-coordinate values ​​of the multiple measured centering coordinates as the linear positioning accuracy of the aperture in the X-axis direction; The deviation value of the Y coordinate value of the plurality of measured centering coordinates which deviates the most from the Y coordinate value of the reference centering coordinate is determined as the linear positioning accuracy of the aperture in the Y-axis direction.

8. The detection method according to claim 1, characterized in that: The electron beam detection device has a plurality of apertures arranged at intervals, each of the apertures corresponding to one of the reference centering coordinates; In the step S2, the distance between the initial coordinate and the reference centering coordinate of the aperture to be detected is greater than or equal to the minimum distance between any two of the plurality of apertures.

9. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the steps of the method for detecting the aperture positioning accuracy according to any one of claims 1 to 8 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method for detecting the aperture positioning accuracy according to any one of claims 1 to 8 are implemented.

11. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method for detecting the aperture positioning accuracy according to any one of claims 1 to 8.

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