Probe adjustment method for electron beam inspection apparatus and related products

Abstract

The application provides a probe adjustment method for an electron beam detection device and related products. The adjustment method comprises obtaining detection parameter electron beam control parameters of the electron beam detection device, the detection parameter electron beam control parameters being used to adjust beam spot diaphragm aperture parameters and / or beam current condenser parameters of an electron beam of the electron beam detection device; and determining a target probe gain corresponding to the detection parameter electron beam control parameters by using a pre-established gain model, the gain model being used to describe a corresponding relationship between the detection parameter electron beam control parameters of the electron beam detection device and an ideal gain of a probe. The adjustment method automatically adjusts the probe gain according to an application scenario of the electron beam detection device, and achieves the purpose of improving the efficiency and accuracy of semiconductor detection.

Description

Technical Field

[0001] This invention relates to the field of semiconductor detection technology, and in particular to a detector adjustment method for an electron beam detection device, a computer-readable storage medium, a computer program product, and an electron beam detection device. Background Technology

[0002] In the chip manufacturing process, critical dimension measurement and defect detection are crucial aspects of integrated circuit yield management. Related technologies typically use electron beam inspection equipment (such as scanning electron microscopes) to inspect wafers and detect defects promptly during wafer manufacturing.

[0003] Electron beam inspection equipment obtains inspection images of wafers using an electron beam. Specifically, the wafer surface bombarded by the electron beam excites physical signals such as secondary electrons and backscattered electrons. These signals are collected and amplified by a detector, then converted from analog to digital to obtain an inspection image. Electron beam inspection equipment can typically switch the beam current intensity. When using a low beam current, the total amount of secondary electrons generated on the sample surface is low, thus requiring a higher detector gain to obtain an inspection image with good signal-to-noise ratio. Conversely, when using a high beam current, a lower detector gain is required to obtain an inspection image with good signal-to-noise ratio. Too low a gain will result in a poor signal-to-noise ratio in the inspection image, while too high a gain will cause detector oversaturation, resulting in an overexposed inspection image.

[0004] As chip manufacturing processes continue to upgrade, in order to inspect wafers more comprehensively and accurately, electron beam inspection equipment needs to frequently switch between small and large beam currents. This requires adjusting the detector gain at any time to obtain inspection images with better signal-to-noise ratio.

[0005] In related technologies, inspectors need to manually adjust the gain of the detector. On the one hand, the adjustment efficiency is low and cannot meet the large-scale inspection needs of wafer fabs. On the other hand, it leads to unstable quality of the inspection images, affecting the accuracy of the inspection. Summary of the Invention

[0006] One object of the present invention is to provide a detector adjustment method, a computer-readable storage medium, a computer program product, and an electron beam detection device for use in electron beam detection equipment, so as to realize automatic adjustment of detector gain according to the application scenario of electron beam detection equipment, thereby improving the efficiency and accuracy of semiconductor detection.

[0007] Specifically, according to one aspect of the present invention, the present invention provides a detector adjustment method for an electron beam detection device, comprising:

[0008] Obtain the electron beam control parameters of the electron beam detection device, wherein the electron beam control parameters are used to adjust the beam spot and / or beam current of the electron beam in the electron beam detection device;

[0009] A target gain corresponding to the electron beam control parameters is determined using a pre-established gain model, which describes the correspondence between the electron beam control parameters and the ideal gain of the detector.

[0010] Optionally, the process of establishing the gain model includes:

[0011] The experimental data of the electron beam detection device are collected, including the aperture, condenser lens excitation and corresponding gain settings.

[0012] The experimental data are fitted using a preset fitting algorithm, and the resulting functional relationship is used as the gain model.

[0013] Optionally, the process of establishing the gain model includes:

[0014] With the excitation of the condenser lens of the electron beam detection device remaining unchanged, multiple sets of experimental data are collected, including the aperture and the corresponding gain setting value.

[0015] The experimental data from multiple sets are fitted, and the functional relationship between the obtained gain setting value and the aperture is used as the gain model.

[0016] Optionally, the experimental data also includes measured beam current, and the method for obtaining the functional relationship between the gain setpoint and the aperture includes:

[0017] By fitting multiple sets of experimental data, the functional relationship between the measured beam current and the aperture is obtained, as well as the functional relationship between the gain setting value and the measured beam current is obtained.

[0018] Based on the functional relationship between the measured beam current and the aperture and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the aperture is obtained.

[0019] Optionally, the process of establishing the gain model includes:

[0020] With the aperture of the electron beam detection device remaining unchanged, multiple sets of experimental data are collected, including condenser lens excitation and corresponding gain setting values.

[0021] The experimental data from multiple sets are fitted, and the functional relationship between the obtained gain setting value and the excitation of the condenser lens is used as the gain model.

[0022] Optionally, the experimental data also includes measured beam current, and the method for obtaining the functional relationship between the gain setpoint and the excitation of the condenser lens includes:

[0023] By fitting multiple sets of experimental data, the functional relationship between the measured beam current and the excitation of the condenser lens is obtained, as well as the functional relationship between the gain setting value and the measured beam current.

[0024] Based on the functional relationship between the measured beam current and the excitation of the condenser lens, and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the excitation of the condenser lens is obtained.

[0025] Optionally, the process of establishing the gain model includes:

[0026] Acquire historical experimental data of the electron beam detection device, including data on aperture, condenser lens excitation, measured beam current and corresponding gain settings recorded during multiple effective detection processes;

[0027] By fitting the historical experimental data, the functional relationship between the measured beam current and the aperture and the excitation of the condenser lens is obtained, as well as the functional relationship between the gain setting value and the measured beam current is obtained.

[0028] Based on the functional relationship between the measured beam current and the aperture and the condenser lens excitation, and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the aperture and the condenser lens excitation is obtained and used as the gain model.

[0029] According to another aspect of the present invention, a computer-readable storage medium is also provided, on which a computer program is stored, wherein the computer program, when executed by a processor, implements the steps of the detector adjustment method for an electron beam detection device described above.

[0030] According to another aspect of the present invention, a computer program product is also provided, comprising a computer program that, when executed by a processor, implements the steps of the detector adjustment method for an electron beam detection device described above.

[0031] According to another aspect of the present invention, an electron beam detection device is also provided, comprising a condenser lens, an aperture, a detector, and a controller, wherein the controller includes a memory, a processor, and a computer program stored in the memory, and the processor, when executing the computer program, implements the steps of the detector adjustment method for the electron beam detection device described above.

[0032] The detector adjustment method for electron beam detection equipment of the present invention obtains the correspondence between electron beam control parameters and the ideal gain of the detector by pre-establishing a gain model. By acquiring the electron beam control parameters and inputting them into the gain model, the detector can be automatically adjusted according to the obtained target gain, thereby obtaining a detection image with good saturation and a good signal-to-noise ratio. Compared with manual detector gain adjustment, this method realizes automatic adjustment of detector gain according to the application scenario of the electron beam detection equipment, thereby improving the efficiency and accuracy of semiconductor detection.

[0033] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0034] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0035] Figure 1 This is a schematic flowchart of an adjustment method according to an embodiment of the present invention;

[0036] Figure 2 This is a flowchart illustrating the adjustment method according to an embodiment of the present invention, which establishes a gain model using experimental data.

[0037] Figure 3 This is a schematic flowchart illustrating the functional relationship between the gain setting value and the aperture aperture in an adjustment method according to an embodiment of the present invention.

[0038] Figure 4 This is a flowchart illustrating the functional relationship between the gain setting value and the aperture aperture in an adjustment method according to another embodiment of the present invention.

[0039] Figure 5 This is a flowchart illustrating the functional relationship between the gain setting value and the condenser lens excitation in an adjustment method according to an embodiment of the present invention.

[0040] Figure 6 This is a flowchart illustrating the functional relationship between the gain setting value and the condenser lens excitation in an adjustment method according to another embodiment of the present invention.

[0041] Figure 7 This is a flowchart illustrating the adjustment method according to an embodiment of the present invention, which establishes a gain model using historical experimental data.

[0042] Figure 8This is a schematic diagram of an electron beam detection device according to an embodiment of the present invention;

[0043] Figure 9 This is a schematic diagram of a computer program product according to an embodiment of the present invention;

[0044] Figure 10 This is a schematic diagram of a computer-readable storage medium according to an embodiment of the present invention. Detailed Implementation

[0045] The purpose of the detector adjustment method for electron beam detection equipment in this embodiment is to automatically adjust the detector gain according to the application scenario of the electron beam detection equipment, thereby improving the efficiency and accuracy of semiconductor detection.

[0046] Figure 1 This is a schematic flowchart of a detector adjustment method for an electron beam detection device according to an embodiment of the present invention. The method generally includes:

[0047] S100, Obtain the electron beam control parameters of the electron beam detection device. The electron beam control parameters are used to adjust the beam spot and / or beam current of the electron beam in the electron beam detection device.

[0048] S200 uses a pre-established gain model to determine the target gain corresponding to the electron beam control parameters. The gain model is used to describe the correspondence between the electron beam control parameters and the ideal gain of the detector.

[0049] Electron beam inspection equipment can be scanning electron microscopes (SEM), transmission electron microscopes (TEM), etc. The object to be inspected can be a semiconductor product, such as a wafer. Electron beam inspection equipment can be used to measure critical dimensions during wafer manufacturing and to detect wafer manufacturing defects.

[0050] Taking a scanning electron microscope (SEM) as an example, an SEM typically includes components such as an electron source, condenser lens, aperture, objective lens, sample stage, and detector. The electron source emits an electron beam; different electron sources can be used as needed. When the electron beam irradiates the surface of the wafer being inspected, it excites physical signals such as secondary electrons and backscattered electrons. These signals are collected and amplified by the detector, then converted from analog to digital to obtain an electron image. The condenser lens typically changes the beam current and affects the beam spot by adjusting its excitation magnitude. The aperture typically changes the beam spot and affects the beam current by adjusting its aperture size. The detector typically changes the amplification of the received physical signals by adjusting its gain, thereby altering the saturation of the detected image.

[0051] Taking secondary electrons as an example, the electron beam current affects the total number of excited secondary electrons. When using a low-current electron beam, the total number of secondary electrons generated on the surface of the wafer under test is low, so the detector gain needs to be adjusted to a higher value to obtain an image with a good signal-to-noise ratio. Conversely, when using a high-current electron beam, the detector gain needs to be adjusted to a lower value to obtain an image with a good signal-to-noise ratio. Low gain leads to poor image signal-to-noise ratio, while high gain leads to detector oversaturation, resulting in overexposed images.

[0052] In this embodiment, the electron beam control parameters may include the current of the electron source, the total emission current of the electron source, the accelerating voltage, the aperture, the condenser lens excitation, and the objective lens excitation. When the wafer is the object to be tested, the current of the electron source, the total emission current, and the accelerating voltage are generally fixed parameters. By adjusting the aperture, the condenser lens excitation, and the objective lens excitation, the electron beam current can be easily and accurately changed, thereby changing the total amount of secondary electrons generated on the surface of the wafer to be tested.

[0053] When inspecting wafers using a scanning electron microscope (SEM), wafers manufactured using different processes or different regions of the same process may require different beam currents. Therefore, for different inspection scenarios, the SEM needs to frequently adjust the aperture or condenser excitation and, in conjunction with adjusting the detector gain, to obtain inspection images with good saturation and a good signal-to-noise ratio.

[0054] In this embodiment, a gain model is pre-established to describe the correspondence between electron beam control parameters and the ideal gain of the detector. The ideal gain is the gain corresponding to a detection image with good saturation and a good signal-to-noise ratio. The gain model can be a functional relationship. For example, the gain model can be a functional relationship between the aperture and the ideal gain, a functional relationship between the condenser lens excitation and the ideal gain, or a functional relationship between the aperture and the condenser lens excitation and the ideal gain, etc. The functional relationship can be obtained through theoretical calculation or by fitting experimental data. The gain model can also be a deep learning model, for example, obtained by training a deep learning algorithm on historical data.

[0055] Scanning electron microscopes (SEMs) can be configured with a controller. When inspecting a wafer, for example, after placing the wafer on a stage, before the electron source emits the electron beam, the relevant units of the SEM set and acquire electron beam control parameters as needed, such as aperture, condenser lens excitation, and objective lens excitation, and send these parameters to the controller. The controller, based on the received electron beam control parameters and a pre-established gain model, obtains the target gain and then uses this target gain to set the detector. Next, the electron beam is used to inspect the wafer, and the detector produces an optimal inspection image.

[0056] The detector adjustment method for electron beam detection equipment of the present invention obtains the correspondence between electron beam control parameters and ideal detector gain by pre-establishing a gain model. By acquiring the electron beam control parameters and inputting them into the gain model, the detector can be automatically adjusted according to the obtained target gain, thereby obtaining a detection image with good saturation and signal-to-noise ratio. Compared with manual detector gain adjustment, this method realizes automatic adjustment of detector gain according to the application scenario of electron beam detection equipment, thereby improving the efficiency and accuracy of semiconductor detection.

[0057] In some embodiments of the detector adjustment method of the present invention, such as Figure 2 As shown, the process of establishing the gain model includes:

[0058] S311, collects experimental data from the electron beam detection equipment, including the aperture, condenser lens excitation and the corresponding gain setting value of the detector;

[0059] S313, use a preset fitting algorithm to fit the experimental data, and use the obtained functional relationship as the gain model.

[0060] Scanning electron microscopes typically have multiple apertures with fixed sizes, allowing for rapid switching of aperture sizes.

[0061] For example, when acquiring experimental data, the aperture, condenser lens excitation, and detector gain can be initially set. Then, the surface of the wafer under test is irradiated with an electron beam to acquire an initial detection image. The detector gain is then gradually adjusted using a preset method until the best-quality detection image is obtained, and the corresponding gain value is recorded as the gain setpoint. For instance, an automatic control device can adjust the detector gain in ascending order, and a pre-established image recognition algorithm can be used to identify the saturation of the detection image corresponding to each gain value. When a detection image that does not overexpose is found, this image is taken as the best-quality detection image, and its corresponding gain value is used as the gain setpoint. Next, the aperture and condenser lens excitation are adjusted sequentially, and the corresponding gain setpoints are recorded.

[0062] After obtaining a sufficient number of sets of experimental data, a preset fitting algorithm can be used to fit the experimental data, with the gain setting value as the ideal gain, to obtain the correspondence between the aperture, the excitation of the condenser lens and the ideal gain of the detector.

[0063] It should be understood that the experimental data used to fit the above functional relationship can be collected through experiments or obtained from historical detection data; there are no restrictions here.

[0064] In some embodiments of this application, the above-described data acquisition steps can be repeated. For the same aperture and condenser lens excitation, multiple gain settings can be acquired, and the average of these multiple gain settings can be used as the ideal gain to obtain the functional relationship, thereby reducing experimental errors and improving the accuracy of the gain model.

[0065] In some embodiments of the detector adjustment method of the present invention, such as Figure 3 As shown, the process of establishing the gain model includes:

[0066] S321. Under the condition that the excitation of the condenser lens of the electron beam detection device remains unchanged, multiple sets of experimental data are collected. The experimental data include the gain setting values ​​corresponding to the aperture and the detector.

[0067] S323 fits multiple sets of experimental data and uses the obtained gain setting value and the functional relationship between the aperture as the gain model.

[0068] In practical applications of scanning electron microscopy (SEM) for wafer inspection, it is not always necessary to simultaneously adjust the condenser excitation and aperture. In some cases, adjusting only the aperture is sufficient to obtain an appropriate total amount of secondary electrons, resulting in a higher quality inspection image. This embodiment simplifies the functional relationship of the gain model.

[0069] Specifically, when acquiring experimental data, while keeping the condenser lens excitation constant, the aperture is first set to its initial value (e.g., x1), and the detector gain is also set to its initial value. Then, the surface of the wafer under test is irradiated with an electron beam to acquire an initial detection image. The detector gain is then adjusted in a preset sequence until the best quality detection image is obtained, and the corresponding gain value is recorded as the gain setting value (e.g., z1). Next, the apertures are adjusted sequentially (e.g., x2, x3, x4, x5, etc.), and the corresponding gain setting values ​​(e.g., z2, z3, z4, z5, etc.) are recorded respectively.

[0070] After obtaining a sufficient number of sets of experimental data, a preset fitting algorithm can be used to fit the experimental data, with the gain setting value as the ideal gain, to obtain the correspondence between the aperture and the ideal gain of the detector.

[0071] In some embodiments of the detector adjustment method of the present invention, such as Figure 4 As shown, the experimental data also includes the methods for obtaining the functional relationship between the measured beam current, gain setpoint, and aperture, including:

[0072] S331. Under the condition that the excitation of the condenser lens of the electron beam detection device remains unchanged, multiple sets of experimental data are collected. The experimental data include the aperture, the measured beam current and the corresponding gain setting value of the detector.

[0073] S333, by fitting multiple sets of experimental data, the functional relationship between the measured beam current and the aperture is obtained, as well as the functional relationship between the gain setting value and the measured beam current is obtained;

[0074] S335. Based on the functional relationship between the measured beam current and the aperture and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the aperture is obtained.

[0075] The total amount of secondary electrons is directly related to the beam current. The aperture size does not directly affect the total amount of secondary electrons, but rather indirectly affects it by influencing the beam spot and beam current. As in the previous embodiment, directly fitting the functional relationship between the aperture and the gain setting requires collecting a large amount of experimental data, making the fitting process quite difficult. This embodiment aims to further simplify the function fitting process and improve the accuracy of the gain model.

[0076] In this embodiment, the measured beam current of the electron beam can be obtained using a Faraday cup. Specifically, when acquiring experimental data, while keeping the excitation of the condenser lens unchanged, the aperture is first set to an initial value (e.g., x1), and the detector gain is set to an initial value. Then, the surface of the wafer to be inspected is irradiated with an electron beam to obtain an initial detection image. The detector gain value is then adjusted in a preset sequence until the detection image of the best quality is obtained. The corresponding gain value is recorded as the gain setting value (e.g., z1), and the corresponding measured beam current (e.g., y1) is also recorded. Next, the apertures (e.g., x2, x3, x4, x5, etc.) are adjusted one by one, and the corresponding measured beam currents (e.g., y2, y3, y4, y5, etc.) and gain setting values ​​(e.g., z2, z3, z4, z5, etc.) are recorded respectively.

[0077] After obtaining a sufficient number of sets of experimental data, the data of the aperture and the measured beam current are first fitted using a preset fitting algorithm to obtain the functional relationship between the measured beam current and the aperture (e.g., y = f(x), where y represents the measured beam current and x represents the aperture).

[0078] Next, a preset fitting algorithm is used to fit the data of the measured beam current and the gain setpoint to obtain the functional relationship between the gain setpoint and the measured beam current (e.g., z = g(y), where z represents the ideal gain).

[0079] Finally, the two functions are combined to obtain the functional relationship between the gain setting value and the aperture (e.g., z = g(f(x))).

[0080] It's important to understand that in some cases, the functional relationship between the gain setpoint and the measured beam current can also be used to guide the adjustment of the detector gain. However, the measured beam current is data that can only be obtained after the scanning electron microscope has started emitting an electron beam. For applications where the scanning electron microscope has not yet started emitting an electron beam, it is still necessary to use the functional relationship between the gain setpoint and the aperture to guide the adjustment of the detector gain.

[0081] In some embodiments of the detector adjustment method of the present invention, such as Figure 5 As shown, the process of establishing the gain model includes:

[0082] S341, while keeping the aperture of the electron beam detection device unchanged, collect multiple sets of experimental data, including the excitation of the condenser lens and the corresponding gain setting value of the detector.

[0083] S343, fits multiple sets of experimental data, and uses the obtained gain set value and the functional relationship between the condenser lens excitation as the gain model.

[0084] In existing technologies, switching the aperture of the diaphragm requires a moving mechanism, which is cumbersome and has low adjustment efficiency. In contrast, adjusting the excitation of the condenser lens is simpler and more efficient.

[0085] Specifically, when acquiring experimental data, while keeping the aperture constant, the condenser lens excitation is first set to an initial value (e.g., i1), and the detector gain is also set to an initial value. Then, the surface of the wafer under test is irradiated with an electron beam to acquire an initial detection image. The detector gain is then adjusted in a preset sequence until the best quality detection image is obtained, and the corresponding gain value is recorded as the gain setting value (e.g., z1). Next, the condenser lens excitation is adjusted item by item (e.g., i2, i3, i4, i5, etc.), and the corresponding gain setting values ​​(e.g., z2, z3, z4, z5, etc.) are recorded respectively.

[0086] After obtaining a sufficient number of sets of experimental data, a preset fitting algorithm can be used to fit the experimental data, with the gain setting value as the ideal gain, to obtain the correspondence between the excitation of the condenser lens and the ideal gain of the detector.

[0087] In some embodiments of the detector adjustment method of the present invention, such as Figure 6 As shown, the experimental data also includes measured beam current, and the methods for obtaining the functional relationship between the gain setpoint and the condenser lens excitation include:

[0088] S351. With the aperture of the electron beam detection device remaining unchanged, multiple sets of experimental data are collected. The experimental data include condenser lens excitation, measured beam current and corresponding gain setting value of the detector.

[0089] S353, by fitting multiple sets of experimental data, the functional relationship between the measured beam current and the excitation of the condenser lens is obtained, as well as the functional relationship between the gain set value and the measured beam current is obtained;

[0090] S355. Based on the functional relationship between the measured beam current and the condenser lens excitation, and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the condenser lens excitation is obtained.

[0091] This embodiment aims to further simplify function fitting and improve the accuracy of the gain model. Specifically, when acquiring experimental data, while keeping the condenser lens excitation constant, the condenser lens excitation is first set to an initial value (e.g., i1), and the detector gain is also set to an initial value. Then, the surface of the wafer to be inspected is irradiated with an electron beam to acquire an initial detection image. The detector gain value is then adjusted in a preset sequence until the detection image of the best quality is obtained. The corresponding gain value is recorded as the gain setting value (e.g., z1), and the corresponding measured beam current (e.g., y1) is also recorded. Next, the condenser lens excitation is adjusted item by item (e.g., i2, i3, i4, i5, etc.), and the corresponding measured beam current (e.g., y2, y3, y4, y5, etc.) and gain setting values ​​(e.g., z2, z3, z4, z5, etc.) are recorded respectively.

[0092] After obtaining a sufficient number of sets of experimental data, the data of the condenser lens excitation and the measured beam current are first fitted using a preset fitting algorithm to obtain the functional relationship between the measured beam current and the condenser lens excitation (e.g., y = p(i), where y represents the measured beam current and i represents the condenser lens excitation).

[0093] Next, a preset fitting algorithm is used to fit the data of the measured beam current and the gain setpoint to obtain the functional relationship between the gain setpoint and the measured beam current (e.g., z = g(y), where z represents the ideal gain).

[0094] Finally, the two functions are combined to obtain the functional relationship between the gain setting value and the condenser excitation (e.g., z = g(p(i))).

[0095] In some embodiments of the detector adjustment method of the present invention, such as Figure 7 As shown, the process of establishing the gain model includes:

[0096] S361, acquire historical experimental data of the electron beam detection equipment, including data on aperture, condenser excitation, measured beam current and corresponding gain settings of the detector recorded during multiple effective detection processes.

[0097] S363, by fitting historical experimental data, obtains the functional relationship between the measured beam current and the aperture and condenser lens excitation, as well as the functional relationship between the gain set value and the measured beam current;

[0098] S365, based on the functional relationship between the measured beam current and the excitation of the aperture and condenser lens, and the functional relationship between the gain setpoint and the measured beam current, obtains the functional relationship between the gain setpoint and the excitation of the aperture and condenser lens, and uses it as the gain model.

[0099] In this embodiment, historical experimental data can be used to fit the functional relationship between the measured beam current and the aperture and condenser lens excitation (e.g., y = q(x, i), where y represents the measured beam current, x represents the aperture, and i represents the condenser lens excitation), and the functional relationship between the gain setting value and the measured beam current can be obtained (e.g., z = g(y), where z represents the ideal gain). Finally, the functional relationship between the gain setting value and the aperture and condenser lens excitation can be obtained (e.g., z = g(q(x, i))).

[0100] The flowchart provided in this embodiment 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 every case. Furthermore, the method may include additional operations. Within the scope of the technical concept provided by the method in this embodiment, additional variations can be made to the above method.

[0101] It should be understood that in some embodiments, the components may be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods may be implemented using software or firmware stored in memory and executed by a suitable instruction execution system.

[0102] This invention also provides a computer program product 10, a computer-readable storage medium 20, and an electron beam detection device 40. Figure 9 This is a schematic diagram of a computer program product 10 according to an embodiment of the present invention. Figure 10 This is a schematic diagram of a computer-readable storage medium 20 according to an embodiment of the present invention. Figure 8 This is a schematic diagram of an electron beam detection device 40 according to an embodiment of the present invention. The computer program product 10 includes a computer program 11, which, when executed by the processor 32, implements the steps of the detector adjustment method for the electron beam detection device described above. A computer-readable storage medium 20 stores the computer program 11 thereon, which, when executed by the processor 32, implements the steps of the detector adjustment method for the electron beam detection device according to any of the above embodiments. The electron beam detection device 40 may include a condenser lens 41, an aperture 42, a detector 43, and a controller 44. The controller includes a memory 31, a processor 32, and the computer program 11 stored in the memory 31. When the processor 32 executes the computer program, it implements the steps of the detector adjustment method for the electron beam detection device according to any of the above embodiments.

[0103] The computer program 11 used to perform the operations of this invention may be assembly instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, integrated circuit configuration data, or source code or object code written in any combination of one or more programming languages ​​and procedural programming languages. The computer program 11 may execute entirely on the user's computer, partially on the user's computer, as a standalone 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 Wide Area Network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, to perform aspects of this invention, electronic circuits, including, for example, programmable logic circuits, Field-Programmable Gate Arrays (FPGAs), or Programmable Logic Arrays (PLAs), may execute computer-readable program instructions using status information from computer-readable program instructions to personalize the electronic circuits.

[0104] For the purposes of this embodiment, computer program product 10 is a related product that includes computer program 11.

[0105] For the purposes of this embodiment, the computer-readable storage medium 20 is a tangible device capable of holding and storing a computer program 11. It can be any device capable of containing, storing, communicating, propagating, or transmitting the computer program 11 for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable storage medium 20 include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable optical disc read-only memory (CD-ROM), digital versatile disc (DVD), memory stick, floppy disk, mechanical encoding device, and any suitable combination thereof.

[0106] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A detector adjustment method for an electron beam detection device, characterized in that, include: Obtain the electron beam control parameters of the electron beam detection device, wherein the electron beam control parameters are used to adjust the beam spot and / or beam current of the electron beam in the electron beam detection device; A target gain corresponding to the electron beam control parameters is determined using a pre-established gain model. The gain model describes the correspondence between the electron beam control parameters and the ideal gain of the detector. The correspondence is a functional relationship between the aperture of the electron beam detection device and the ideal gain, a functional relationship between the excitation of the condenser lens of the electron beam detection device and the ideal gain, or a functional relationship between the aperture and the excitation of the condenser lens and the ideal gain.

2. The adjustment method according to claim 1, characterized in that, The process of establishing the gain model includes: The experimental data of the electron beam detection device are collected, including the aperture, condenser lens excitation and corresponding gain settings. The experimental data are fitted using a preset fitting algorithm, and the resulting functional relationship is used as the gain model.

3. The adjustment method according to claim 1, characterized in that, The process of establishing the gain model includes: With the excitation of the condenser lens of the electron beam detection device remaining unchanged, multiple sets of experimental data are collected, including the aperture and the corresponding gain setting value. The experimental data from multiple sets are fitted, and the functional relationship between the obtained gain setting value and the aperture is used as the gain model.

4. The adjustment method according to claim 3, characterized in that, The experimental data also includes measured beam current, and the method for obtaining the functional relationship between the gain setpoint and the aperture includes: By fitting multiple sets of experimental data, the functional relationship between the measured beam current and the aperture is obtained, as well as the functional relationship between the gain setting value and the measured beam current is obtained. Based on the functional relationship between the measured beam current and the aperture and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the aperture is obtained.

5. The adjustment method according to claim 1, characterized in that, The process of establishing the gain model includes: With the aperture of the electron beam detection device remaining unchanged, multiple sets of experimental data are collected, including condenser lens excitation and corresponding gain setting values. The experimental data from multiple sets are fitted, and the functional relationship between the obtained gain setting value and the excitation of the condenser lens is used as the gain model.

6. The adjustment method according to claim 5, characterized in that, The experimental data also includes measured beam current, and the method for obtaining the functional relationship between the gain setpoint and the condenser lens excitation includes: By fitting multiple sets of experimental data, the functional relationship between the measured beam current and the excitation of the condenser lens is obtained, as well as the functional relationship between the gain setting value and the measured beam current. Based on the functional relationship between the measured beam current and the excitation of the condenser lens, and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the excitation of the condenser lens is obtained.

7. The adjustment method according to claim 1, characterized in that, The process of establishing the gain model includes: Acquire historical experimental data of the electron beam detection device, including data on aperture, condenser lens excitation, measured beam current and corresponding gain settings recorded during multiple effective detection processes; By fitting the historical experimental data, the functional relationship between the measured beam current and the aperture and the excitation of the condenser lens is obtained, as well as the functional relationship between the gain setting value and the measured beam current is obtained. Based on the functional relationship between the measured beam current and the aperture and the condenser lens excitation, and the functional relationship between the gain setting value and the measured beam current, the functional relationship between the gain setting value and the aperture and the condenser lens excitation is obtained and used as the gain model.

8. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the steps of the detector adjustment method for an electron beam detection device as described in any one of claims 1 to 7.

9. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the steps of the detector adjustment method for an electron beam detection device as described in any one of claims 1 to 7.

10. An electron beam detection device, characterized in that, The device includes a condenser lens, an aperture, a detector, and a controller. The controller includes a memory, a processor, and a computer program stored in the memory. When the processor executes the computer program, it implements the steps of the detector adjustment method for an electron beam detection device as described in any one of claims 1 to 7.

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