Discharge site detection method and discharge site detection device

Abstract

The present application provides a discharge site detection method and a discharge site detection device, which can improve the detection accuracy of discharge. According to one embodiment, a discharge site detection method for a charged particle beam irradiation device alternately having a first mode and a second mode is provided. In the first mode, the beam of charged particles can be deflected by applying voltages to a plurality of electrodes, respectively. In the second mode, no voltage is applied, and data representing the potential of each of the plurality of electrodes during the emission of the beam can be obtained. The discharge site detection method includes, in the second mode, detecting that discharge occurs when the variation in the potential indicated by the data related to any one of the plurality of electrodes exceeds a predetermined threshold value, and detecting the site corresponding to the electrode as a site where discharge occurs.

Description

[0001] This application is based on Japanese Patent Application No. 2021-120646 (filed on July 21, 2021) and enjoys priority of that application. This application incorporates the entire contents of that basic application by reference. Technical Field

[0002] The implementation methods relate to a method for detecting discharge sites and a device for detecting discharge sites. Background Technology

[0003] Photolithography is a process used to form wiring patterns for semiconductor devices, playing a crucial role in semiconductor device manufacturing. In recent years, the linewidth of wiring required for semiconductor devices has been decreasing year by year due to the increasing integration of LSI (Large Scale Integration).

[0004] In the formation of wiring patterns with miniaturized linewidths, a high-precision original pattern (also called an intermediate mask or mask) is used. In the production of this high-precision original pattern, for example, electron beam (hereinafter, also called electron beam) drawing technology with excellent resolution is used. As an apparatus for producing original patterns using electron beam drawing technology, a variable-shape electron beam drawing apparatus (hereinafter, also called an electron beam drawing apparatus) is known.

[0005] An electron beam drawing apparatus shapes an electron beam into various shapes using a variable shaping method, and then irradiates the sample with the shaped electron beam. The original pattern is produced by drawing on the sample through this irradiation.

[0006] Here, sometimes there are insulating components within the electron beam drawing apparatus, and consequently, there may be undesirable insulating materials. These insulating materials may become charged and discharge due to scattered electrons. This discharge generates a transient change in the electric field within the apparatus, which may cause the path of the electron beam to change. This change in the path of the electron beam during drawing can, for example, lead to errors in the drawn pattern.

[0007] To reduce the frequency of such discharges, the location of the discharge cause can be identified and addressed by replacing components. For example, the location of the discharge cause can be determined by visually inspecting or using a microscope to search for discharge traces on components. Furthermore, techniques are known that involve installing a discharge detector within an electron beam mapping apparatus to detect discharges and infer the approximate location of the discharge cause (see, for example, Japanese Patent Application Publication No. 2016-134306 and Japanese Patent Application Publication No. 63-216342).

[0008] However, it is difficult to detect all discharges within an electron beam mapping device using such a discharge detector. For example, if a discharge occurs at a specific electrode of a deflector within the electron beam mapping device, it may sometimes be impossible to detect the discharge. Even if the discharge detector captures changes in the electric field caused by a discharge occurring at a distance from the detector (a current detector acts as an antenna to capture electromagnetic waves caused by the discharge and converts the resulting current change into voltage for measurement), it is difficult to determine the location of the discharge cause. Summary of the Invention

[0009] The present invention was made in view of the above situation, and its purpose is to provide a discharge site detection method and discharge site detection device that can improve the detection accuracy of discharge.

[0010] According to one embodiment of the present invention, a method for detecting discharge sites in a charged particle beam irradiation apparatus capable of switching between a first mode and a second mode is provided. In the first mode, a charged particle beam can be deflected by applying voltages to multiple electrodes respectively. In the second mode, without applying the voltages, data representing the potentials of the multiple electrodes during the emission of the beam can be obtained. The discharge site detection method includes: in the second mode, detecting a discharge if the potential variation shown in the data associated with any one of the multiple electrodes exceeds a predetermined threshold, and detecting the site corresponding to the electrode as a site of discharge. Attached Figure Description

[0011] Figure 1 This is a schematic diagram showing an example of the configuration of the electron beam drawing apparatus of the first embodiment.

[0012] Figure 2 This is a schematic diagram showing an example of the configuration of the illumination deflector of the electron beam drawing apparatus of the first embodiment.

[0013] Figure 3 This is a schematic diagram showing an example of the configuration of the projection deflector of the electron beam drawing apparatus of the first embodiment.

[0014] Figure 4 This is a block diagram illustrating an example of the configuration of the drawing control unit and the discharge detection control unit of the electron beam drawing apparatus according to the first embodiment.

[0015] Figure 5 This is a flowchart illustrating an example of the operation performed by the electron beam mapping apparatus of the first embodiment to detect discharge.

[0016] Figure 6This diagram illustrates how the electron beam is controlled to travel straight from the electron gun toward the worktable side in the electron beam drawing apparatus of the first embodiment.

[0017] Figure 7 This is an example of a graph that shows a curve obtained by depicting multiple voltage data items separately.

[0018] Figure 8 This diagram illustrates how the electron beam is controlled to irradiate a position different from the opening of the second aperture member in the electron beam drawing apparatus of the first embodiment, according to the first modification of the first embodiment.

[0019] Figure 9 This diagram illustrates how the electron beam is controlled to deflect in various directions through the illumination coil in the electron beam drawing apparatus of the second variation of the first embodiment.

[0020] Figure 10 This is a block diagram illustrating an example of the configuration of the discharge detection control unit of the electron beam mapping apparatus in the third modification of the first embodiment.

[0021] Figure 11 This is a flowchart illustrating an example of the operation of detecting discharge performed by the electron beam mapping apparatus of the third variation of the first embodiment.

[0022] Explanation of symbols

[0023] 1: Electron beam drawing device; 10: Drawing section; 100: Electron beam; 101: Electron gun; 102: First aperture component; 103: Illumination coil; 104: Illumination deflector; 105: Second aperture component; 106: Projection coil; 107: Projection deflector; 108: Third aperture component; 109: Objective lens coil; 110: Objective lens deflector; 111: Stage; 11: Drawing control section; 1101: Beam path control section; 12: Voltage / current control section; 13: High voltage power supply; 141, 142, 143: Current detectors; 21: Sample; 30: Discharge detection section; 301: Discharge detector Measurement and control unit; 3011: Voltage data acquisition unit; 3012: Voltage data analysis unit; 30121: Data comparison unit; 302, 305: Signal processing unit; 303: Storage unit; 3031: Voltage data storage unit; 3032: Discharge information storage unit; 3033: Discharge waveform storage unit; 304: Monitor; 41: Faraday cup; 42: Ammeter; P1, P2: Processor; M1, M2: Memory; 1041, 1042, 1071, 1072, 1073, 1074, 1075, 1076, 1077, 1078: Electrodes; 1000, 2000: Areas. Detailed Implementation

[0024] Hereinafter, embodiments will be described with reference to the accompanying drawings. In the following description, constituent elements having the same function and configuration are marked with common reference symbols. When multiple constituent elements sharing a common reference symbol are distinguished, an additional character is added to that common reference symbol for differentiation. When multiple constituent elements do not require special distinction, only the common reference symbol is used to mark those multiple constituent elements without adding an additional character. The embodiments shown below illustrate apparatus and methods for embodying technical concepts; the shape, structure, and arrangement of the constituent components are not limited to those shown.

[0025] Each functional block can be implemented by combining either or both of the hardware and software. Furthermore, it is not necessary to differentiate the functional blocks as described below. For example, a portion of the functionality can be performed by a functional block different from the illustrated functional blocks. Moreover, the illustrated functional blocks can be divided into more refined functional sub-blocks. Additionally, the names of the functional blocks and components in the following description are for convenience only and do not limit the structure or operation of the functional blocks and components.

[0026] <First Implementation>

[0027] The following description uses a charged particle beam irradiation apparatus, which includes the discharge site detection apparatus of this embodiment, as a non-limiting example to illustrate an electron beam mapping apparatus. However, this embodiment is not limited to this. For example, the technology disclosed in this embodiment can also be applied to other apparatuses using charged particle beams such as electron beams and ion beams. These apparatuses include, for example, converging ion beam mapping apparatuses, original pattern inspection apparatuses, electron microscopes, and electrolytic emission ion microscopes. The beams used in these apparatuses are not limited to single beams and can also be multiple beams.

[0028] [Example of composition]

[0029] (1) Electron beam mapping device

[0030] Figure 1 This is a schematic configuration diagram showing an example of the configuration of the electron beam drawing apparatus 1 according to the first embodiment. Figure 1 The configuration of the electron beam drawing apparatus 1 shown in the figure is only one example, and the configuration of the electron beam drawing apparatus 1 is not limited to the configuration shown in the figure. For example, in addition to the configuration shown in the figure, the electron beam drawing apparatus 1 may also include other constituent elements that can be normally provided in an electron beam drawing apparatus. Furthermore, the respective arrangements of the constituent elements of the electron beam drawing apparatus 1 may also differ from the arrangements shown in the figure.

[0031] The electron beam drawing apparatus 1 includes, for example, a drawing unit 10, a drawing control unit 11, a voltage / current control unit 12, and a high-voltage power supply 13.

[0032] The drawing unit 10 includes an electron gun 101, a first aperture component 102, an illumination coil 103, an illumination deflector 104, a second aperture component 105, a projection coil 106, a projection deflector 107, a third aperture component 108, an objective lens coil 109, an objective lens deflector 110, and a stage 111. A sample 21 can be fixed on the stage 111. The electron beam drawing apparatus 1 uses an electron beam 100 emitted from the electron gun 101 to draw the sample 21 fixed on the stage 111.

[0033] Hereinafter, two directions parallel to, for example, orthogonal to the surface of the fixed sample 21 in the worktable 111 will be defined as the X direction and the Y direction, respectively. The direction intersecting this surface and moving from this surface toward the electron gun 101 will be defined as the Z direction. The Z direction will be described as being orthogonal to the X and Y directions, but this is not necessarily a limitation. Hereinafter, the Z direction will be described as "up" and the direction opposite to the Z direction will be described as "down", but this description is only for convenience and is, for example, unrelated to the direction of gravity.

[0034] A high-voltage power supply 13 is connected to the electron gun 101, applying a high voltage to the electron gun 101. Based on the application of this high voltage, an electron beam 100 is emitted from the electron gun 101. The drawing control unit 11 includes, for example, a processor P1 and a memory M1. The processor P1 is, for example, a CPU (Central Processing Unit). The memory M1 is a memory such as ROM (Read Only Memory) or RAM (Random Access Memory) used to store programs and / or data. The drawing control unit 11 sends a control signal to the voltage / current control unit 12. Based on this control signal, the voltage / current control unit 12 controls, for example, the voltage applied to each electrode included in each of the illumination deflector 104, projection deflector 107, and objective lens deflector 110, thereby controlling the electric field in the area through which the electron beam 100 passes. Based on the control signal, the voltage / current control unit 12 controls, for example, the current flowing in each of the illumination coil 103, projection coil 106 and objective lens coil 109, thereby controlling the magnetic field of the area through which the electron beam 100 passes.

[0035] Between the electron gun 101 and the worktable 111, a first aperture component 102, a second aperture component 105 and a third aperture component 108 are arranged sequentially from top to bottom.

[0036] An opening is provided, for example, in the first aperture member 102. This opening is located, for example, at the distribution center of the current distribution of the electron beam 100 on the upper surface of the first aperture member 102.

[0037] An illumination coil 103 and an illumination deflector 104 are disposed, for example, between a first aperture member 102 and a second aperture member 105. The second aperture member 105 has, for example, a rectangular opening. The illumination deflector 104 includes, for example, two electrodes. By changing the electric field of the region sandwiched by these electrodes, the illumination deflector 104 can change the path of the electron beam 100 after passing through the opening of the first aperture member 102. For example, by changing the path, the electron beam drawing device 1 can be in either a beam-on state or a beam-off state. In the beam-on state, a portion of the electron beam 100 passes through the opening in the second aperture member 105. In the beam-off state, the entire electron beam 100 does not pass through the opening. The electron beam 100 after passing through the second aperture member 105 is shaped into, for example, a rectangle corresponding to the opening. For example, the electron beam mapping device 1 can be in a beam-on state while a voltage of 0V is applied to each electrode of the illumination deflector 104 and the path of the electron beam 100 is not altered by the illumination deflector 104. The illumination coil 103, for example, a beam-adjusting deflector coil also called an alignment coil, is configured to surround the illumination deflector 104. The illumination coil 103 can change the path of the electron beam 100 by altering the nearby magnetic field. Control of this path change via the illumination coil 103 can also be used, for example, for fine-tuning of the path after the illumination deflector 104 has controlled the path.

[0038] The illumination coil 103 is configured to surround the illumination deflector 104, causing a change in the electric field of the region sandwiched by the electrodes of the illumination deflector 104, thereby changing the path of the electron beam 100 after passing through the opening of the first aperture member 102. However, the configuration of the illumination coil 103 is not limited to these configurations, and the illumination coil 103 can be configured at any position within the drawing section 10.

[0039] A projection coil 106 and a projection deflector 107 are disposed, for example, between a second aperture member 105 and a third aperture member 108. An opening is provided in the third aperture member 108. The projection deflector 107 includes, for example, eight electrodes. By changing the electric field of the region sandwiched by these electrodes, the projection deflector 107 can change the path of the electron beam 100 after passing through the opening of the second aperture member 105. By changing this path, the projection deflector 107 controls the position of the electron beam 100 projected onto a plane including the upper surface of the third aperture member 108. A portion of the electron beam 100 projected onto this plane that is projected onto the opening of the third aperture member 108 passes through the third aperture member 108. Through this control, the shape and size of the electron beam 100 passing through the third aperture member 108 can be changed. For example, if a voltage of 0V is applied to each electrode of the projection deflector 107 and the path of the electron beam 100 is not altered by the projection deflector 107, the entire electron beam 100 can pass through the opening of the third aperture member 108. The projection coil 106, for example, a beam adjustment deflection coil also referred to as an alignment coil, is configured to surround the projection deflector 107. The projection coil 106 can change the path of the electron beam 100 by changing the nearby magnetic field. Control of this path change via the projection coil 106 can also be used, for example, for fine-tuning of the path after the projection deflector 107 has controlled the path.

[0040] The projection coil 106, by being configured to surround the projection deflector 107, causes a change in the electric field of the region sandwiched by the electrodes of the projection deflector 107, thereby changing the path of the electron beam 100 after passing through the opening of the second aperture member 105. However, the configuration of the projection coil 106 is not limited to these configurations, and the projection coil 106 can be configured at any position within the drawing section 10.

[0041] Objective lens coil 109 and objective lens deflector 110 are disposed, for example, between third aperture member 108 and stage 111. Stage 111 is capable of continuous movement in both the X and Y directions. Objective lens deflector 110 includes, for example, eight electrodes. Objective lens deflector 110 can change the path of electron beam 100 after passing through the opening of third aperture member 108 by changing the electric field of the region sandwiched by these electrodes. Objective lens deflector 110 controls the position of the electron beam 100 irradiating the sample 21 on the continuously moving stage 111 by changing the path. Objective lens coil 109, for example, is a beam adjustment deflection coil also called an alignment coil, and is disposed to surround objective lens deflector 110. Objective lens coil 109 can change the path of electron beam 100 by changing the nearby magnetic field. The control of this path change by objective lens coil 109 can also be used for fine adjustment of the path after the objective lens deflector 110 controls the path.

[0042] The objective coil 109, by surrounding the electrodes of the objective deflector 110, changes the electric field in the region sandwiched by the electrodes of the objective deflector 110, thereby changing the path of the electron beam 100 after passing through the opening of the third aperture member 108. However, the configuration of the objective coil 109 is not limited to these configurations, and the objective coil 109 can also be configured at any position within the drawing section 10.

[0043] A Faraday cup 41 is provided at a position on the worktable 111 that is different from the position of the fixed sample 21. The Faraday cup 41 is connected to a galvanometer 42, for example. The Faraday cup 41 and the galvanometer 42 can be prepared separately from the electron beam mapping apparatus 1, or they can be included in the electron beam mapping apparatus 1.

[0044] The Faraday cup 41 is capable of capturing electrons from the electron beam 100. A galvanometer 42 measures the current corresponding to the captured electrons. The galvanometer 42, for example, sends a signal indicating the magnitude of the measured current to the drawing control unit 11.

[0045] Within the drawing section 10, insulators and the like may become charged and discharge due to scattered electrons from the electron beam 100. For the purpose of detecting such discharges, the electron beam drawing apparatus 1 may also include the following configuration.

[0046] The drawing unit 10 may include current detectors 141, 142, and 143. Current detectors 141, 142, and 143 are, for example, metal plates serving as antennas. Current detector 141 is, for example, disposed between the first aperture member 102 and the illumination deflector 104. Current detector 142 is, for example, disposed between the illumination deflector 104 and the second aperture member 105. Current detector 142 detects current by capturing reflected electrons from the electron beam 100 reflected by the second aperture member 105 while deflecting the beam. The detected current value is used to adjust the beam's passage position to a desired location. Current detector 143 is, for example, disposed between the projection deflector 107 and the third aperture member 108. The configuration of each current detector is not limited to these; each current detector can be disposed at any position within the drawing unit 10. Each current detector can detect changes in the electric field near the current detector due to discharge (the current detector acts as an antenna, capturing electromagnetic waves from the discharge and converting the resulting current change into voltage, which is then measured).

[0047] The electron beam mapping apparatus 1 also includes a discharge detection unit 30. The discharge detection unit 30 can be prepared separately from the electron beam mapping apparatus 1, but in this case, it can be connected to the electron beam mapping apparatus 1. Alternatively, a configuration formed by arbitrarily combining the components of the electron beam mapping apparatus 1 that are related to discharge detection can be called a discharge location detection device. For example, a discharge location detection device includes an illumination deflector 104, a projection deflector 107, multiple electrodes in the objective lens deflector 110, and the discharge detection unit 30.

[0048] The discharge detection unit 30 includes a discharge detection control unit 301, signal processing units 302A, 302B, and 302C, a storage unit 303, and a monitor 304. Figure 1 The diagram shows that the discharge detection unit 30 also includes a signal processing unit 305, but the signal processing unit 305 will be described in a modified example described later.

[0049] The discharge detection control unit 301 performs control related to discharge detection. The discharge detection control unit 301 includes, for example, a processor P2 and a memory M2. The processor P2 is, for example, a CPU. The memory M2 is a memory such as ROM or RAM used to store programs and / or data.

[0050] Signal processing units 302 are, for example, oscilloscopes. Each electrode of the illumination deflector 104 can be electrically connected to either the signal processing unit 302A or the voltage / current control unit 12. In this specification, the state in which each electrode is connected to the signal processing unit is called sensor mode, and the state in which each electrode is connected to the voltage / current control unit 12 is called deflection mode. Each electrode of the illumination deflector 104 is connected to the signal processing unit 302A, for example, via a MOS transistor. The electrical connection between the electrode and the signal processing unit 302A is controlled by a control signal applied to the gate of the transistor. This control signal is, for example, supplied by the discharge detection control unit 301. Similarly, each electrode of the projection deflector 107 can be electrically connected to the signal processing unit 302B, and each electrode of the objective lens deflector 110 can be electrically connected to the signal processing unit 302C.

[0051] The storage unit 303 is composed of a storage medium such as a non-volatile memory that can be written to and read from at any time, such as an HDD (Hard Disc Drive) or an SSD (Solid State Drive).

[0052] Signal processing unit 302A acquires analog data of current based on the potential of an electrode connected to it, performs analog-to-digital conversion on the analog data, and stores the resulting data item (hereinafter also referred to as a voltage data item) in storage unit 303. This voltage data item, for example, represents the relationship between the potential of the electrode and time. Hereinafter, for simplicity, the electrode will be referred to as the electrode corresponding to the voltage data item, and the voltage data item as the voltage data item corresponding to the electrode. The same applies to the following descriptions. When signal processing unit 302A is electrically connected to multiple electrodes, for example, it acquires analog data items of current for the same actual time period for all connected electrodes. For each electrode, signal processing unit 302A generates a voltage data item as described above and stores the generated voltage data item in storage unit 303. The same applies to signal processing units 302B and 302C. It can also be determined whether voltage data items generated by different signal processing units 302 are voltage data items within the same substantially the same time period. Therefore, for example, the clocks used by signal processing units 302A, 302B, and 302C can be the same clock, or they can be clocks that can be synchronized with each other. Furthermore, "substantially the same" means that they do not necessarily have to be identical, and errors that may occur when they are generated or manufactured identically are allowed. The same applies to the following aspects of "the same". In this specification, the terms "store" and "record" can be used interchangeably in relation to this storage association of voltage data items by the storage unit 303.

[0053] The discharge detection control unit 301 reads one or more voltage data items stored in the storage unit 303. Based on these voltage data items, it performs discharge detection processing to detect changes in the electric field from the discharge (a current detector acts as an antenna to capture electromagnetic waves from the discharge, converting the resulting current change into voltage and measuring the change). The result of this processing is stored in the storage unit 303. The result of this processing stored in the storage unit 303 is displayed, for example, on the monitor 304. Alternatively, the relationship between potential and time represented by the one or more voltage data items stored in the storage unit 303 can also be displayed on the monitor 304. Discharge detection processing can also be performed based on this display on the monitor 304.

[0054] (2) Deflector

[0055] Figure 2 This is a schematic configuration diagram showing an example of the configuration of the illumination deflector 104 in the electron beam mapping apparatus 1 of the first embodiment. Figure 2 For example, a diagram showing the illumination deflector 104 viewed from above is provided.

[0056] The illumination deflector 104 includes electrodes 1041 and 1042. Figure 2 The illustration shows an illumination deflector 104 consisting of two electrodes, but this embodiment is not limited to the illustration. Electrodes 1041 and 1042 may be arranged in shapes and / or configurations other than those shown in the illustration, and the illumination deflector 104 may also consist of a number of electrodes other than two.

[0057] The upper ends of electrodes 1041 and 1042 are located at substantially the same position in the Z direction, for example. The lower ends of electrodes 1041 and 1042 are located at substantially the same position in the Z direction, for example.

[0058] Electrodes 1041 and 1042 are, for example, spaced apart along the X direction. Electrodes 1041 and 1042 are respectively plate-shaped, extending, for example, along the Y and Z directions. In this case, for example, the length of electrode 1041 in the Y direction is longer than its length in the X direction, and the length of electrode 1041 in the Z direction is also longer. The same applies to electrode 1042. The lengths of electrodes 1041 and 1042 in the X, Y, and Z directions are, for example, substantially the same.

[0059] The voltage / current control unit 12 controls the electric field in the region between electrodes 1041 and 1042 by applying voltages to electrodes 1041 and 1042 respectively. The electron beam 100 passes through this region after passing through the opening of the first aperture member 102. Figure 2 An example of a region within this region, in a plane parallel to the X and Y directions, through which the electron beam can pass, is shown as region 1000.

[0060] Figure 3 This is a schematic configuration diagram showing an example of the configuration of the projection deflector 107 in the electron beam mapping apparatus 1 of the first embodiment. Figure 3 The diagram shown, for example, illustrates the projection deflector 107 as viewed from above. The configuration of the projection deflector 107 will be described below, but the objective lens deflector 110 can also have the same configuration as the projection deflector 107. The objective lens deflector 110 can also have the same configuration as the projection deflector 107, with multiple layers overlapping in the Z direction.

[0061] The projection deflector 107 includes electrodes 1071, 1072, 1073, ... and 1078. In Figure 3 The illustration shows a projection deflector 107 consisting of eight electrodes, but this embodiment is not limited to the illustration. Electrodes 1071, 1072, 1073, ... and 1078 may be arranged in shapes and / or configurations other than those shown in the illustration, and the projection deflector 107 may also be composed of a number of electrodes other than eight.

[0062] The upper ends of any combination or all of electrodes 1071, 1072, 1073, ... and 1078 are respectively located in substantially the same position in the Z direction. The lower ends of any combination or all of electrodes 1071, 1072, 1073, ... and 1078 are respectively located in substantially the same position in the Z direction.

[0063] The orientation of each electrode around a straight line (hereinafter also referred to as the reference line) parallel to the Z direction will be explained. For example, the electron beam 100 can also pass through the reference line even when it is not deflected by the illumination coil 103, illumination deflector 104, projection coil 106, and projection deflector 107. Electrodes 1071, 1072, 1073, ..., 1078 are positioned in different directions when viewed from the reference line. Hereinafter, the direction 0° from the reference line toward, for example, the X direction will be used for explanation, using an angle with counterclockwise rotation as positive when viewed from above.

[0064] For example, the reference point in electrode 1071 is located at 0° around the reference line. The reference point is, for example, the point where the center or center of gravity of electrode 1071 is located. The same applies below when using the term "reference point" for other electrodes. For example, the reference point in electrode 1072 is located at 45° around the reference line. For example, the reference point in electrode 1073 is located at 90° around the reference line. For example, the reference point in electrode 1074 is located at 135° around the reference line. For example, the reference point in electrode 1075 is located at 180° around the reference line. For example, the reference point in electrode 1076 is located at 225° around the reference line. For example, the reference point in electrode 1077 is located at 270° around the reference line. For example, the reference point in electrode 1078 is located at 315° around the reference line.

[0065] Electrode 1071 is, for example, a flat plate extending along the Y and Z directions. In this case, for example, the length of electrode 1071 in the Y direction is longer than the length in the X direction, and the length of electrode 1071 in the Z direction is also longer. Hereinafter, for the sake of simplicity, the surfaces of a flat plate electrode, such as the surfaces extending along the Y and Z directions, that are longer than one of the directions will be referred to as flat plate surfaces.

[0066] Electrodes 1072, 1073, ..., and 1078 are also identical to electrode 1071, being flat plates whose lengths in the other two directions are longer than the length in one of the other directions. (See reference...) Figure 2As explained in the description of the relationship between electrodes 1041 and 1042, any combination or all of electrodes 1071, 1072, 1073, ... and 1078 may also have substantially the same dimensions.

[0067] For example, the distance from the reference line to any combination or all of the reference points of electrodes 1071, 1072, 1073, ... and 1078 is substantially the same. For example, the straight line from the reference line toward the reference point of electrode 1071 intersects the flat surface of electrode 1071 perpendicularly. The same applies to electrodes 1072, 1073, ... and 1078.

[0068] The voltage / current control unit 12 applies voltages to electrodes 1071, 1072, 1073, ..., and 1078 respectively, thereby controlling the electric field of the region surrounded by electrodes 1071, 1072, 1073, ..., and 1078. The electron beam 100, after passing through the opening of the second aperture member 105, passes through this region. Figure 3 An example of a region within this region, in a plane parallel to the X and Y directions, through which the electron beam can pass, is denoted as region 2000.

[0069] (3) Drawing control unit and discharge detection control unit

[0070] This section describes an example of a discharge detection process performed by the discharge detection control unit 301.

[0071] Figure 4 This is a block diagram illustrating an example of the configuration of the drawing control unit 11 and the discharge detection control unit 301 of the electron beam drawing apparatus 1 according to the first embodiment.

[0072] The drawing control unit 11 includes, for example, a beam path control unit 1101. The discharge detection control unit 301 includes, for example, a voltage data acquisition unit 3011 and a voltage data analysis unit 3012. The drawing control unit 11 and the discharge detection control unit 301 respectively implement the processing functions of each unit by causing the processor P to execute programs stored in the memory M. Furthermore, the processing functions are not limited to those implemented using programs stored in the memory M. For example, the processing functions could also be implemented using programs provided via a network.

[0073] Storage unit 303 includes, for example, voltage data storage unit 3031 and discharge information storage unit 3032.

[0074] The voltage data storage unit 3031 stores voltage data items.

[0075] The discharge information storage unit 3032 stores information about the results of the discharge detection processing performed by the discharge detection control unit 301.

[0076] The beam path control unit 1101, for example, sends a control signal related to the control of the path of the electron beam 100 during discharge detection processing to the voltage / current control unit 12. Based on this control signal, the voltage / current control unit 12 controls the electric field and / or magnetic field within the drawing unit 10 as described above.

[0077] During the emission of the electron beam 100 under the control of the electric field and / or magnetic field, the voltage data acquisition unit 3011 performs a process of sending a voltage data processing request to any signal processing unit 302. Based on the voltage data processing request, the signal processing unit 302 generates a voltage data item and stores it in the voltage data storage unit 3031 as described above. The voltage data acquisition unit 3011 then performs a process of reading a specific voltage data item stored in the voltage data storage unit 3031.

[0078] The voltage data analysis unit 3012 performs a process to determine whether a discharge has been detected near the electrode corresponding to the voltage data item based on the voltage data item. More specifically, as described below. When a peak value appears at the electrode in the voltage data item and the magnitude of the potential change at the peak value exceeds a threshold, the voltage data analysis unit 3012 determines that a discharge has been detected; otherwise, it determines that no discharge has been detected. Alternatively, the voltage data analysis unit 3012 may perform this determination process based, for example, on the analysis of the high-frequency components of the potential change. When a discharge is determined to be detected, the voltage data analysis unit 3012 can perform a process to determine the relationship between the voltage and time represented by the voltage data item and to establish the time corresponding to the voltage of the peak value related to the determination.

[0079] The voltage data analysis unit 3012 performs the process of storing the result of determining whether the above-mentioned discharge has been detected in the discharge information storage unit 3032. When the voltage data acquisition unit 3011 reads multiple voltage data items from the voltage data storage unit 3031, the voltage data analysis unit 3012 performs the same determination process on each of the multiple voltage data items and stores the result of the determination in the discharge information storage unit 3032.

[0080] The voltage data analysis unit 3012 performs the aforementioned determination on voltage data items corresponding to two or more electrodes within substantially the same time period, and if it determines that a discharge is detected near a certain electrode, it can perform the following processing. These two or more electrodes are, for example, contained in the same deflector, but are not limited to this. Based on these voltage data items, the voltage data analysis unit 3012 performs processing to determine one of the two or more electrodes. Alternatively, the voltage data analysis unit 3012 can also perform this determination processing for one or more voltage data items where a discharge is determined to be detected, using information identifying the time of the determination. In this determination processing, for example, it determines the electrode closer to the location of the discharge cause, such as an insulator, or the closest electrode. The voltage data analysis unit 3012 performs processing to store the information of the identified electrode in the discharge information storage unit 3032.

[0081] The voltage data analysis unit 3012 can perform processing to infer the location where a discharge occurred based on the identified electrode. For example, it can infer that there is an insulator in the voltage supply line (e.g., cable) from the voltage / current control unit 12 to the identified electrode, and that a discharge occurred at the insulator. Alternatively, it can infer that an insulator is attached to the identified electrode, and that a discharge occurred at the insulator. Or, it can infer that a discharge occurred at a location in space within a certain distance from the identified electrode, closer to the identified electrode than any of the other electrodes of the two or more electrodes. This distance can also be based on the aforementioned threshold. For example, the larger the threshold, the smaller the distance. When a peak value of the electrode potential appears in multiple voltage data items corresponding to the two or more electrodes, the location can be inferred as follows. For example, the electrode corresponding to the voltage data item with the larger peak value is closer to the location where a discharge occurred, and the location where the discharge occurred is inferred. In this way, the location associated with the identified electrode (hereinafter also referred to as the location corresponding to the identified electrode) is detected as the location where a discharge occurred. The voltage data analysis unit 3012 performs the process of storing the identified and inferred location information in the discharge information storage unit 3032.

[0082] [Action Example]

[0083] A specific operation of detecting discharge performed by the electron beam mapping apparatus 1 will be described in detail. For example, this operation is performed in a state where each electrode of the illumination deflector 104 is electrically connected to the signal processing unit 302A, each electrode of the projection deflector 107 is electrically connected to the signal processing unit 302B, and each electrode of the objective lens deflector 110 is electrically connected to the signal processing unit 302C (sensor mode). Hereinafter, the connection of each electrode will be described, but this embodiment is not limited to this.

[0084] (1) Overall process of actions related to discharge detection and processing

[0085] Figure 5 This is a flowchart illustrating an example of the operation performed by the electron beam drawing apparatus 1 of the first embodiment.

[0086] In step ST00, the discharge detection control unit 301, for example, switches the connection destination of each electrode of the projection deflector 107 from the voltage / current control unit 12 to the signal processing unit 302B. The switch from this deflection mode to the sensor mode is, for example, a switch of electrical connections, as shown in reference... Figure 1 As explained, this can also be achieved based on control signals from the discharge detection control unit 301. Furthermore, switching the connection destinations of each electrode of the projection deflector 107 can also be achieved by physically replacing the connection wiring. The same applies to the following: Similarly, the connection destinations of each electrode of the illumination deflector 104 are switched to the signal processing unit 302A, and the connection destinations of each electrode of the objective lens deflector 110 are switched to the signal processing unit 302C.

[0087] In step ST01, the drawing control unit 11, under the control of the beam path control unit 1101, controls the path of the electron beam 100 emitted from the electron gun 101. More specifically, as described below. Under the control of the beam path control unit 1101, the drawing control unit 11 sends a control signal to the voltage / current control unit 12. Based on this control signal, the voltage / current control unit 12 controls the electric field and / or magnetic field of the area through which the electron beam 100 passes. The path of the electron beam 100 corresponds to the control of this electric field and / or magnetic field. Under the control of the beam path control unit 1101, the drawing control unit 11, for example, controls the electron beam 100 to travel straight from the electron gun 101 toward the stage 111. Hereinafter, an example of the case where the electron beam 100 is controlled to travel straight will be described. Furthermore, after step ST02, the processing related to the electrodes included in the projection deflector 107 will be described as an example. However, the same treatment can be performed on the electrodes included in the illumination deflector 104 and / or the objective lens deflector 110, either instead of or in parallel with this treatment.

[0088] In step ST02, the discharge detection control unit 301, under the control of the voltage data acquisition unit 3011, acquires, for example, voltage data items corresponding to the electrodes included in the projection deflector 107. More specifically, as described below. Under the control of the voltage data acquisition unit 3011, the discharge detection control unit 301 sends a voltage data processing request to the signal processing unit 302B, for example, during the period when the electron beam 100 is emitted under the aforementioned control. Based on the voltage data processing request, the signal processing unit 302B generates voltage data items corresponding to the electrodes included in the projection deflector 107. The generated voltage data items are, for example, within substantially the same time period. The generated voltage data items, for example, represent, in at least a portion, the relationship between voltage and time during the period when the electron beam 100 is emitted under the aforementioned control. The discharge detection control unit 301, under the control of the voltage data acquisition unit 3011, acquires the generated voltage data items. Furthermore, it is not necessary to acquire all of these voltage data items. Operations after step ST03 are performed, for example, during the period when the electron beam 100 is emitted under the aforementioned control, but this is not mandatory.

[0089] In step ST03, under the control of the voltage data analysis unit 3012, the discharge detection control unit 301 determines, for example, whether a discharge is detected near the electrode corresponding to the voltage data item in each of the voltage data items corresponding to the electrodes included in the projection deflector 107 within substantially the same time period.

[0090] If no discharge is detected in any voltage data item, the operation ends. However, if a discharge is detected near a certain electrode, the process proceeds to step ST04.

[0091] In step ST04, under the control of the voltage data analysis unit 3012, the discharge detection control unit 301 determines, based on these voltage data items, the electrode among the electrodes included in the projection deflector 107 that is closest to the cause of discharge. The following processing is performed in this determination process: For example, if it is determined in step ST03 that a discharge is detected in only one voltage data item, the discharge detection control unit 301 determines the electrode corresponding to that voltage data item. For example, if it is determined in step ST03 that a discharge is detected in two or more voltage data items, the discharge detection control unit 301, as described later, compares the peak height and / or timing related to the determination among the voltage data items where the discharge was detected.

[0092] In step ST05, under the control of the voltage data analysis unit 3012, the discharge detection control unit 301 deduces the location where a discharge occurred based on the identified electrode and terminates the operation. For example, if there is an insulator in the voltage supply line from the voltage / current control unit 12 to the identified electrode, it is deduced that a discharge occurred at that insulator. Alternatively, if an insulator is attached to the identified electrode, it is deduced that a discharge occurred at that insulator. Or, it is deduced that a discharge occurred at a location in the space within a certain distance from the identified electrode that is closer to the identified electrode than any of the other electrodes included in the projection deflector 107. Thus, the location corresponding to the identified electrode is detected as the location where a discharge occurred.

[0093] In the above description, the actions after step ST02 were explained using the processing related to the electrodes included in the projection deflector 107 as an example, but this embodiment is not limited to this. As described above, the same processing can be performed on the electrodes included in two or more deflectors in the actions after step ST02. In this case, in step ST04, for example, the electrode among the electrodes included in the two or more deflectors that is closest to the location of the discharge cause is determined. In this case, in step ST05, for example, it is presumed that a discharge occurred at a location in the space within a certain distance from the determined electrode that is closer to the determined electrode than any of the other electrodes included in the two or more deflectors. Alternatively, if a peak value of the electrode potential appears in multiple voltage data items, the following can also be described. In this case, in step ST05, the electrode corresponding to the voltage data item with the larger peak value is closer to the location where the discharge occurred, and the location where the discharge occurred is presumed.

[0094] (2) Details of beam path control processing

[0095] right Figure 5 The details of the beam path control processing in step ST01 are explained.

[0096] Figure 6 This indicates that in the electron beam drawing apparatus 1 of the first embodiment, the electron beam 100 is controlled to travel in a straight line from the electron gun 101 toward the worktable 111. Through this control, the electron beam 100, for example, passes through the openings of the second aperture member 105 and the third aperture member 108 toward the worktable 111. Figure 6 For ease of reference, the illustration of the discharge detection unit 30 is omitted. The same applies to the other identical figures following this one.

[0097] To ensure the electron beam 100 travels in a straight line, the beam path control unit 1101 of the control unit 11 causes the voltage / current control unit 12 to control the magnetic field by, for example, using at least one of the illumination coil 103, projection coil 106, and objective lens coil 109. If electrodes electrically connected to the voltage / current control unit 12 are present in the illumination deflector 104, projection deflector 107, and objective lens deflector 110, the beam path control unit 1101 can cause the voltage / current control unit 12 to control the electric field by applying a voltage to the electrode. The beam path control unit 1101 causes the voltage / current control unit 12 to control the magnetic field and / or the electric field, thereby ensuring the electron beam 100 travels in a straight line as described above.

[0098] like Figure 6 As shown, the stage 111 moves to a position where the electron beam 100 irradiates the Faraday cup 41. The Faraday cup 41 captures electrons from the irradiated electron beam 100, and the galvanometer 42 measures the current corresponding to the captured electrons. The galvanometer 42, for example, sends a signal indicating the magnitude of the measured current to the beam path control unit 1101. The beam path control unit 1101 causes the voltage / current control unit 12 to finely adjust the path of the electron beam 100, for example, using at least one of the illumination coil 103, projection coil 106, and objective lens coil 109, so that the magnitude of the current indicated by the signal becomes maximum.

[0099] In this specification, for example, when the path of the electron beam 100 is controlled in such a way that it is referred to as controlling the electron beam 100 to travel in a straight line by means of the beam path control unit 1101. However, this embodiment is not limited to this. For example, it is not necessary to use the Faraday cup 41 to fine-tune the path of the electron beam 100.

[0100] In the above description, the beam path control unit 1101 has been described as making fine adjustments to the path of the electron beam 100 using at least one of the illumination coil 103, projection coil 106, and objective lens coil 109 based on the magnitude of the current detected using the Faraday cup 41. However, this embodiment is not limited to this. The beam path control unit 1101 may also make fine adjustments to the path of the electron beam 100 using at least one of the illumination coil 103, projection coil 106, and objective lens coil 109 based on any other parameters.

[0101] (3) Details of voltage data analysis and processing

[0102] right Figure 5 The details of voltage data analysis and processing in steps ST03 and ST04 are explained below.

[0103] Figure 7This is an example of a graph obtained by plotting multiple voltage data items over substantially the same time period. These multiple voltage data items, for example, correspond to electrodes 1071, 1072, 1073, and 1074 of the projection deflector 107, respectively. In each graph, the horizontal axis corresponds to time, and the vertical axis corresponds to the potential of the electrode corresponding to the plotted voltage data item. Figure 7 In this example, for ease of reference, graphs are shown for four electrodes of the projection deflector 107, not all of them. The following describes the process of applying graphs to these electrodes of the projection deflector 107. Figure 5 This example illustrates the voltage data analysis and processing in steps ST03 and ST04, but the same processing can also be performed on all electrodes of the projection deflector 107. Alternatively, the same processing can be performed on the illumination deflector 104 and / or the objective lens deflector 110, either instead of the projection deflector 107 or based on the projection deflector 107.

[0104] exist Figure 7 In the graph shown, for example, there are instances where the magnitude of the potential variation of electrodes 1071 and 1072 exceeds a threshold. For example, the magnitude of the potential variation from the peak value that becomes the peak value exceeds the threshold. On the other hand, the magnitude of the potential variation of either electrode 1073 or 1074 does not exceed the threshold. Therefore, in step ST03, it is determined that discharge near electrodes 1071 and 1072 is detected, and it is determined that discharge near electrodes 1073 and 1074 is not detected.

[0105] This determination is made because electrodes 1071 and 1072 are closer to the location of the discharge cause than either electrode 1073 or 1074. Furthermore, the peak value of electrode 1072 is higher than that of electrode 1071, and the timing of the peak value of electrode 1072 is earlier than that of electrode 1071. This is believed to be because electrode 1072 is closer to the location of the discharge cause than electrode 1071. Therefore, in step ST04, for example, the electrode 1072 corresponding to the voltage data item with the highest peak value (e.g., potential) among the voltage data items determined to have detected a discharge is determined. Alternatively, the electrode 1072 corresponding to the voltage data item with the earliest peak value (e.g., potential) among such voltage data items may also be determined.

[0106] For example, the reference process can be repeated after removing the determined electrode 1072 from the electron beam mapping apparatus 1. Figure 5The procedure described is as follows. In this case, for electrodes other than electrode 1072 where a nearby discharge is detected, such as electrode 1071, if it is determined that no discharge is detected near that electrode, it can be confirmed that an environment exists where scattered electrons tend to concentrate at the identified electrode. For example, such an environment may occur if the identified electrode itself is attached to an insulating material that causes the discharge. For example, this confirmation could be performed by removing the electrode corresponding to any voltage data item for which a discharge is detected.

[0107] [Effect]

[0108] In the electron beam mapping apparatus 1 of the first embodiment, for example, each electrode of the illumination deflector 104 is electrically connected to the signal processing unit 302A, each electrode of the projection deflector 107 is electrically connected to the signal processing unit 302B, and each electrode of the objective lens deflector 110 is electrically connected to the signal processing unit 302C. Each signal processing unit 302 generates multiple voltage data items corresponding to the electrodes connected to that signal processing unit. The electron beam mapping apparatus 1 can detect discharges generated near each electrode of the illumination deflector 104, the projection deflector 107, and the objective lens deflector 110 based on these voltage data items. Among the detected discharges, discharges that cannot be detected by the current detector (which is also called an intermediate detector to distinguish it from the Faraday cup 41, which is a current detector) conventionally provided in the electron beam mapping apparatus 1 may also be included. The electron beam mapping apparatus 1 is a device that significantly increases the number of discharge detection sites. Therefore, according to the electron beam mapping apparatus 1, more discharges can be detected within the apparatus, and the location of the discharge cause can be inferred over a wider area. By setting a larger threshold for discharge detection processing, the electron beam mapping apparatus 1 can detect discharges occurring near the electrode corresponding to that voltage data item when a discharge is detected, and / or discharges that, if occurring during mapping, are more likely to cause errors in the mapping pattern. Furthermore, it can be confirmed that the electrode itself corresponding to the voltage data item where a discharge was detected is the cause of the discharge.

[0109] The electron beam mapping apparatus 1, for example, can determine the electrode closer to the discharge cause or the closest electrode among two or more electrodes based on voltage data items corresponding to each electrode within substantially the same time period. These two or more electrodes are, for example, contained in the same deflector. Based on the determined electrode, the electron beam mapping apparatus 1 can infer the location where the discharge occurred. Thus, according to the electron beam mapping apparatus 1, the region inferred to be the cause of the discharge can be further narrowed. Furthermore, it can be confirmed that the determined electrode itself is the cause of the discharge.

[0110] For example, such a discharge detection process is performed while the electron beam 100 is controlled to travel straight from the electron gun 101 toward the stage 111. In this case, the electron beam 100 passes between the two electrodes 1041 and 1042 of the illumination deflector 104, through the area surrounded by the eight electrodes 1071, 1072, ..., and 1078 of the projection deflector 107, and further through the area surrounded by, for example, eight electrodes of the objective lens deflector 110. Even if there is a site near any of these electrodes that could cause a discharge, the scattered electrons of the electron beam 100 can be concentrated at that site to generate a discharge. Such a discharge is detected in the discharge detection process. Therefore, according to the electron beam mapping apparatus 1, even if there is a site near any of these electrodes that could cause a discharge, the presence of that site can be captured without omission by the discharge detection process.

[0111] [Variation Example]

[0112] Other operations performed by the electron beam mapping apparatus 1 to detect discharge will be explained. For each variation, the explanation will focus on the differences from the above-described configuration examples, operation examples, and effects.

[0113] (1) First variation

[0114] In the electron beam mapping apparatus 1 of the first modification of the first embodiment, in Figure 5 In the beam path control process of step ST01, the path of the electron beam 100 is controlled as follows.

[0115] Figure 8 This indicates that in the electron beam drawing apparatus 1 of the first modification of the first embodiment, the electron beam 100 is controlled to irradiate a position different from the opening of the second aperture member 105.

[0116] To direct the electron beam 100 to such a position, the beam path control unit 1101 of the control unit 11 causes the voltage / current control unit 12 to control, for example, the magnetic field by using the illumination coil 103. Furthermore, it is not necessary for the entire electron beam 100 to be directed to a position different from the opening of the second aperture member 105; a portion of the electron beam 100 may also pass through the opening of the second aperture member 105. If there are electrodes in the illumination deflector 104 electrically connected to the voltage / current control unit 12, the beam path control unit 1101 can cause the voltage / current control unit 12 to control the electric field by applying a voltage to the electrodes. The beam path control unit 1101 causes the voltage / current control unit 12 to control the aforementioned magnetic field change and / or electric field change, so that the electron beam 100 is directed to irradiate as described above.

[0117] After step ST02, for example, the voltage data items corresponding to any one of the electrodes electrically connected to the signal processing unit 302 among the electrodes included in the illumination deflector 104 and / or projection deflector 107 are processed.

[0118] Generally, the electron beam drawing apparatus 1 operates for a period much longer than the beam-on state until completion of drawing on the sample 21. During the beam-off state, the electron beam 100 irradiates a position different from the opening of the second aperture member 105 without passing through that opening. For example, during the beam-off state, scattered electrons concentrate at locations prone to discharge. During the beam-on state, discharge occurs due to these concentrated scattered electrons, resulting in, for example, drawing pattern errors. The electron beam drawing apparatus 1 of the first modification of the first embodiment performs a discharge detection process during the period when the electron beam 100 is controlled to irradiate a position different from the opening of the second aperture member 105. That is, the discharge detection process is performed during the period when the electron beam 100 is irradiated in the same way as during the beam-off state. Therefore, according to the electron beam drawing apparatus 1 of the first modification of the first embodiment, discharges from locations particularly prone to discharge can be detected during drawing on the sample 21.

[0119] (2) Second variation

[0120] In the electron beam mapping apparatus 1 of the second modification of the first embodiment, in Figure 5 In the beam path control process of step ST01, the path of the electron beam 100 is controlled as follows.

[0121] Figure 9 In the electron beam drawing apparatus 1 of the second variation of the first embodiment, the electron beam 100 is controlled to deflect in various directions by means of the illumination coil 103. In this control, the electron beam 100 can deflect in any direction at any time. In this control, the electron beam 100 can also deflect more than when deflected by the illumination coil 103 and the illumination deflector 104 when drawing onto the sample 21. In this control, the electron beam 100 can also deflect in directions other than those deflected by the illumination coil 103 and the illumination deflector 104 when drawing onto the sample 21.

[0122] The following describes an example of the case where the electron beam 100 is controlled in this way, but the same applies when the electron beam 100 is controlled to deflect in various directions by the projection coil 106 or the objective lens coil 109.

[0123] The beam path control unit 1101 of the control unit 11 causes the voltage / current control unit 12 to control, for example, the magnetic field change using the illumination coil 103, so that the electron beam 100 is deflected. In the case where there is an electrode in the illumination deflector 104 electrically connected to the voltage / current control unit 12, the beam path control unit 1101 can also cause the voltage / current control unit 12 to control the electric field change by applying a voltage to that electrode. The beam path control unit 1101 causes the voltage / current control unit 12 to control the aforementioned magnetic field change and / or the electric field change, so that the electron beam 100 is deflected as described above.

[0124] After step ST02, for example, the voltage data items corresponding to any one of the electrodes electrically connected to the signal processing unit 302 among the electrodes included in the illumination deflector 104 and / or projection deflector 107 are processed.

[0125] The electron beam mapping apparatus 1 of the second modification of the first embodiment performs discharge detection processing while controlling the electron beam 100 to deflect in various directions. Because the electron beam 100 is deflected in various directions, electrons are scattered over a wide range within the electron beam mapping apparatus 1. Therefore, the electron beam mapping apparatus 1 of the second modification of the first embodiment can detect discharges from locations that are the cause of discharge, even those located over a wider range.

[0126] In the above, in each of the first and second modifications, regarding Figure 5 Other examples of beam path control processing in step ST01 have been described. The electron beam drawing apparatus 1 can also perform actions that arbitrarily combine and execute several examples of beam path control processing disclosed in this specification. For example, in Figure 5 In step ST03, if no discharge is detected in any voltage data item, the operation does not end and returns to step ST01. In the beam path control processing performed upon returning to step ST01, different control is performed than in the beam path control processing performed before returning to step ST01. For example, if in the initial step ST01 the electron beam 100 is controlled to travel straight from the electron gun 101 towards the worktable 111, in the next step ST01, the electron beam 100 may be controlled to deflect in various directions by the illumination coil 103, etc.

[0127] During discharge detection, as in the first modification described above, a portion of the electron beam 100 can pass through the opening of the second aperture member 105, while the remaining portion is shielded by the second aperture member 105. Furthermore, in the second modification, a portion of the electron beam 100 can also pass through the opening of the third aperture member 108, while the remaining portion is shielded by the third aperture member 108.

[0128] (3) Third variation

[0129] Figure 10 This is a block diagram illustrating an example of the configuration of the discharge detection and control unit 301 of the electron beam mapping apparatus 1 in the third modification of the first embodiment.

[0130] If already Figure 1 As shown in the diagram, the discharge detection unit 30 includes a signal processing unit 305. Current detectors 141, 142, and 143 are electrically connected to the signal processing unit 305.

[0131] The signal processing unit 305 uses an I / V amplifier (not shown) to convert the current from the current detector 141 into a voltage and measures this voltage (voltage data item). Thus, the signal processing unit 305 can obtain the current from the current detector 141 by measuring the voltage (voltage data item) corresponding to the current. Alternatively, it can measure the voltage generated at the input impedance (resistance) of the I / V amplifier using an oscilloscope in a horizontal (parallel) configuration to measure the voltage (voltage data item) corresponding to the current from the current detector 141. The signal processing unit 305 also similarly measures the voltage (voltage data items) corresponding to the currents from current detectors 142 and 143. In this way, the voltage data items from the signal processing unit 305 correspond to the current values ​​from the current detectors. The signal processing unit 305 generates voltage data items corresponding to current detectors 141, 142, and 143 respectively and stores them in the storage unit 303.

[0132] For example, the voltage data item corresponding to current detector 141 represents the relationship between the potential and time corresponding to the current detected by current detector 141. The same applies to the voltage data items corresponding to current detectors 142 and 143, respectively. It is possible to determine whether voltage data items generated by different signal processing units are voltage data items within substantially the same time period. Therefore, for example, the clocks used by signal processing unit 305 and signal processing units 302A, 302B, and 302C can be the same clock, or they can be clocks that can be synchronized with each other.

[0133] Voltage data acquisition unit 3011, for example, refer to Figure 4 As described, the process of sending voltage data processing requests to any signal processing unit 302 and also to signal processing unit 305 is performed. Based on the voltage data processing requests, signal processing unit 305 generates voltage data items corresponding to current detectors 141, 142, and 143 respectively and stores them in voltage data storage unit 3031. The voltage data items generated by signal processing units 302 and 305 based on these voltage data processing requests are, for example, voltage data items within substantially the same time period.

[0134] For reference Figure 4 As explained, for example, based on multiple voltage data items generated by the signal processing unit 302 and stored in the voltage data storage unit 3031, the voltage data analysis unit 3012 performs discharge detection processing and determines the electrode near the location of the discharge cause. Furthermore, as referred to... Figure 4 As explained, the voltage data analysis unit 3012 can perform processing to infer the location where the discharge occurred based on the identified electrodes.

[0135] The voltage data acquisition unit 3011 reads the voltage data items stored in the voltage data storage unit 3031 that correspond to the current detectors 141, 142, and 143, respectively. The voltage data analysis unit 3012, for example, determines whether a waveform from the discharge has been captured in the waveform of the potential-time relationship shown in the voltage data item corresponding to the current detector 141 (hereinafter also referred to as the waveform of the voltage data item). For example, even if a peak occurs in the voltage data item at the current detector 141, and the magnitude of the potential change at that peak does not exceed the aforementioned threshold, it may be determined that the voltage data item has captured a waveform from the discharge. If the voltage data analysis unit 3012 determines that a waveform from the discharge has been captured, it establishes a correspondence between the voltage data item and the discharge near the determined electrode, and stores the data in the discharge waveform storage unit 3033 of the storage unit 303. Hereinafter, for simplicity, this correspondence establishment will be described as establishing a correspondence between the voltage data item and the electrode. The voltage data analysis unit 3012 performs the same processing on the voltage data items corresponding to the current detectors 142 and 143, respectively. Hereinafter, we will describe how voltage data items are mapped to discharges near the determined electrodes, but this embodiment is not limited to this. For example, if the location where a discharge occurs is predicted, the voltage data analysis unit 3012 may also perform the processing of mapping voltage data items to discharges occurring at that predicted location and storing the mapping in the discharge waveform storage unit 3033.

[0136] When the above process is repeated, the discharge waveform storage unit 3033 stores, for example, voltage data items (hereinafter also referred to as discharge waveform data items) corresponding to each electrode of the illumination deflector 104, projection deflector 107, and objective lens deflector 110, respectively. Furthermore, it is not necessary to store all discharge waveform data items corresponding to each of the current detectors 141, 142, and 143 as discharge waveform data items corresponding to a particular electrode. Alternatively, it is also possible to store none of the discharge waveform data items corresponding to a particular electrode. Furthermore, it is also possible to store multiple discharge waveform data items corresponding to a particular current detector and corresponding to a particular electrode.

[0137] Instead of performing the determination process for a specific electrode as described above, or based on the determination process, as referred to... Figure 4 As explained, the condition is determined to be a discharge detected near a certain electrode, and / or as referred to Figure 7 As explained, it has been confirmed that even in an environment where electrons are easily concentrated and scattered at a certain electrode, the discharge waveform data items can still be stored in the discharge waveform storage unit 3033.

[0138] After storing the discharge waveform data items in the discharge waveform storage unit 3033, the discharge detection control unit 301 performs the processing described below. The processing can also be performed during the drawing of the sample 21.

[0139] The voltage data acquisition unit 3011 processes the transmission of a voltage data processing request to the signal processing unit 305. Based on the voltage data processing request, the signal processing unit 305 generates voltage data items (hereinafter also referred to as checked voltage data items) corresponding to current detectors 141, 142, and 143 respectively, and stores them in the voltage data storage unit 3031. The voltage data acquisition unit 3011 then reads the checked voltage data item corresponding to a specific current detector stored in the voltage data storage unit 3031.

[0140] The voltage data analysis unit 3012 includes a data comparison unit 30121.

[0141] The data comparison unit 30121 reads a discharge waveform data item corresponding to the current detector from the discharge waveform storage unit 3033. For example, the data comparison unit 30121 determines whether the waveform of the voltage data item being checked is similar to the waveform of the discharge waveform data item. If the data comparison unit 30121 determines that the waveform of the voltage data item being checked is similar to the waveform of the discharge waveform data item, it determines that a discharge has been detected near the electrode corresponding to the discharge waveform data item. The data comparison unit 30121 stores the determination result in the discharge information storage unit 3032. If one or more other discharge waveform data items corresponding to the current detector are stored in the discharge waveform storage unit 3033, the data comparison unit 30121 performs the same processing on those other discharge waveform data items. The data comparison unit 30121 also performs the same processing on the voltage data items being checked corresponding to other current detectors. The determination result stored in the discharge information storage unit 3032 is displayed on the monitor 304, for example.

[0142] Next, for example, a detailed description will be given of the operation of detecting the discharge generated near the electrodes of any one of the illumination deflector 104, projection deflector 107 and objective lens deflector 110, performed by the electron beam drawing apparatus 1 of the third variation of the first embodiment, in the drawing of the sample 21.

[0143] Figure 11 This is a flowchart illustrating an example of the operation performed by the electron beam drawing apparatus 1 of the third variation of the first embodiment.

[0144] Step ST10 and Figure 5 Step ST00 is the same, and step ST11 is the same. Figure 5 The steps are the same as ST01.

[0145] In step ST12, the discharge detection control unit 301 performs, under the control of the voltage data acquisition unit 3011, the discharge detection control unit 301. Figure 5The operation described in step ST02 is performed, and voltage data items corresponding to current detectors 141, 142, and 143 are acquired respectively. More specifically, as follows: Under the control of the voltage data acquisition unit 3011, during the period when the electron beam 100 is emitted under the aforementioned control, the discharge detection control unit 301 sends a voltage data processing request to the signal processing unit 302B and also sends a voltage data processing request to the signal processing unit 305. Based on the voltage data processing request, the signal processing unit 305 generates voltage data items corresponding to current detectors 141, 142, and 143 respectively. The voltage data items generated by the signal processing units 302B and 305 based on these voltage data processing requests are, for example, voltage data items within substantially the same time period. Under the control of the voltage data acquisition unit 3011, the discharge detection control unit 301 acquires voltage data items corresponding to the electrodes included in the projection deflector 107 and voltage data items corresponding to current detectors 141, 142, and 143 respectively. In addition, it is not necessary to obtain all the voltage data items corresponding to current detectors 141, 142 and 143 respectively.

[0146] In step ST13, the discharge detection control unit 301, under the control of the voltage data analysis unit 3012, performs discharge detection processing based on the voltage data items corresponding to the electrodes included in the projection deflector 107. In this discharge detection processing, for example, the following steps are performed: Figure 5 The actions described in steps ST03 and ST04 are performed, but it is not mandatory to perform the actions described in step ST04. For example, the electrode 1072, which is closest to the cause of discharge among the electrodes included in the projection deflector 107, is identified.

[0147] In step ST14, under the control of the voltage data analysis unit 3012, the discharge detection control unit 301 stores the discharge waveform data item in the discharge waveform storage unit 3033. More specifically, as described below. Under the control of the voltage data analysis unit 3012, the discharge detection control unit 301 determines, for example, whether a waveform from the discharge has been captured for the waveform of the voltage data item corresponding to the current detector 141. If, under the control of the voltage data analysis unit 3012, a waveform from the discharge has been captured, the discharge detection control unit 301 establishes a correspondence between the voltage data item and the determined electrode 1072 and stores it as a discharge waveform data item in the discharge waveform storage unit 3033. The same processing is performed on the voltage data items corresponding to the current detectors 142 and 143 respectively.

[0148] By repeatedly performing steps ST11 to ST14 an arbitrary number of times, the discharge waveform storage unit 3033 stores, for example, each electrode of the illumination deflector 104, projection deflector 107, and objective lens deflector 110, voltage data items (hereinafter also referred to as discharge waveform data items) corresponding to the current detectors 141, 142, and 143 respectively.

[0149] After storing the discharge waveform data items in the discharge waveform storage unit 3033, the actions after step ST20 are executed.

[0150] In step ST20, the discharge detection control unit 301 switches the connection destination of each electrode of the projection deflector 107 from the signal processing unit 302B to the voltage / current control unit 12, for example. Similarly, the connection destination of each electrode of the illumination deflector 104 and the objective lens deflector 110 is also switched to the voltage / current control unit 12.

[0151] In step ST21, for example during the drawing of sample 21, the discharge detection control unit 301, under the control of the voltage data acquisition unit 3011, acquires the voltage data items to be checked corresponding to current detectors 141, 142, and 143, respectively. These acquired voltage data items, for example, represent the relationship between voltage and time during the drawing of sample 21. Furthermore, it is not necessary to acquire all the voltage data items corresponding to current detectors 141, 142, and 143. Operations after step ST22 are performed, for example, during the drawing of sample 21, but this is not mandatory.

[0152] In step ST22, under the control of the data comparison unit 30121, the discharge detection control unit 301 determines whether the waveform of a certain voltage data item under test is similar to the waveform of a certain discharge waveform data item. More specifically, as described below. Under the control of the data comparison unit 30121, the discharge detection control unit 301 reads a certain discharge waveform data item stored in the discharge waveform storage unit 3033, for example, corresponding to the current detector 141. This discharge waveform data item is, for example, associated with the electrode 1072. Under the control of the data comparison unit 30121, the discharge detection control unit 301 determines, for example, whether the waveform of the voltage data item under test corresponding to the current detector 141 is similar to the waveform of the discharge waveform data item. The same processing is performed on each combination of the voltage data item under test and all the discharge waveform data items stored in the discharge waveform storage unit 3033 corresponding to the current detector 141. The same processing is also performed on the voltage data items under test corresponding to the current detectors 142 and 143 respectively.

[0153] If the waveform of a certain voltage data item being checked is determined to be similar to the waveform of a certain discharge waveform data item, proceed to step ST23; otherwise, the operation ends.

[0154] For example, in step ST22, the waveform of the checked voltage data item corresponding to the current detector 143 is described as similar to the waveform of the discharge waveform data item corresponding to the current detector 143 and established with the electrode 1072. In this case, in step ST23, the discharge detection control unit 301, under the control of the data comparison unit 30121, determines that a discharge generated near the electrode 1072 has been detected.

[0155] For example, during the measurement before the drawing device performs the drawing, in step ST12, the discharge detected by each deflector electrode is correlated with the current waveform data of each current detector 141 to 143 during the detection and stored. During the drawing performed by the drawing device, even if the deflector electrode cannot be used as a discharge detector, discharge detection can still be performed by each current detector 141 to 143.

[0156] The above description focuses on the case where a discharge waveform data item corresponding to a specific electrode is used, but this embodiment is not limited to this. As described above, each discharge waveform data item can also correspond to a discharge generated at a previously predicted location. In this case, in step ST13, the following steps are performed: Figure 5 The action described in step ST05 is determined in step ST23 to be a discharge detected at a previously predicted location.

[0157] The electron beam mapping apparatus 1 of the third modification of the first embodiment performs the discharge detection process described up to the second modification, detecting a discharge near an electrode included in the illumination deflector 104, projection deflector 107, and objective lens deflector 110, and performing the following processing: The electron beam mapping apparatus 1 establishes a correspondence between a voltage data item corresponding to any one of the current detectors 141, 142, and 143, which captures a waveform from the discharge, and stores it as a discharge waveform data item. This processing is repeated, for example, preparing discharge waveform data items for the case where a discharge occurs near each electrode of the illumination deflector 104, projection deflector 107, and objective lens deflector 110. Then, the electron beam mapping apparatus 1 of the third modification of the first embodiment detects the discharge as follows: For example, in mapping the sample 21, the electron beam mapping apparatus 1 obtains the voltage data item to be checked corresponding to one of the current detectors 141, 142, and 143. When the waveform of the voltage data item being examined is similar to the waveform of any one of the discharge waveform data items corresponding to the current detector, the electron beam mapping device 1 determines that a discharge has been detected near the electrode that corresponds to the discharge waveform data item.

[0158] Thus, the electron beam mapping apparatus 1 of the third modification of the first embodiment can detect discharges generated near each electrode of the illumination deflector 104, the projection deflector 107, and the objective lens deflector 110 using current detectors 141, 142, and 143. This electron beam mapping apparatus 1 can also acquire voltage data items from each of the current detectors 141, 142, and 143 during the deflection of the electron beam 100 using the illumination deflector 104, the projection deflector 107, and the objective lens deflector 110. Therefore, according to the electron beam mapping apparatus 1 of the third modification of the first embodiment, even during mapping of the sample 21, discharges generated near each electrode of the illumination deflector 104, the projection deflector 107, and the objective lens deflector 110 can be detected.

[0159] (4) Fourth variation

[0160] The description focuses on one of the electrodes included in the illumination deflector 104, projection deflector 107, and objective lens deflector 110. The voltage / current control unit 12 is electrically connected to this electrode via a voltage supply line and applies a voltage to the electrode. Conversely, a signal processing unit 302 is electrically connected to this electrode and obtains information related to the electrode's potential. Regarding the electrical connection to this electrode, the description relates to the output impedance of the voltage / current control unit 12 and the input impedance of the signal processing unit 302.

[0161] For example, the input impedance of the signal processing unit 302 can be adjusted. For example, the signal processing unit 302 is configured to switch the input impedance between several values ​​in advance. This input impedance is, for example, substantially the same as the output impedance of the voltage / current control unit 12. The output impedance of the voltage / current control unit 12 is, for example, the output impedance of the digital-to-analog converter (DAC amplifier) ​​included in the voltage / current control unit 12.

[0162] The signal processing unit 302 is not configured to allow adjustment of the input impedance within the signal processing unit 302 itself. In the electrical connection between the signal processing unit 302 and the electrode, a terminating resistor is clamped on the signal processing unit 302 side. The combination of the signal processing unit 302 and the terminating resistor can also be considered as a signal processing unit where the impedance resulting from the synthesis of the input impedance of the signal processing unit 302 and the terminating resistor is used as the input impedance.

[0163] For example, if the output impedance of the voltage / current control unit 12 is 50Ω and the input impedance of a certain signal processing unit 302 is 1MΩ, a 50Ω terminating resistor is provided as described above. The combination of this signal processing unit 302 and the terminating resistor can be considered as a signal processing unit whose input impedance is the combined resistance of the parallel-connected 1MΩ resistor and the 50Ω resistor, i.e., 49.99…Ω. Therefore, the input impedance of this signal processing unit is, for example, substantially the same as the output impedance of the voltage / current control unit 12.

[0164] In the above description, the output impedance of the voltage / current control unit 12 and the input impedance of the signal processing unit 302 were explained with regard to the connection with a single electrode. The same applies to the other electrodes included in the illumination deflector 104, projection deflector 107, and objective lens deflector 1102. Furthermore, the output impedance of the voltage / current control unit 12 can also be the same for the connections to each electrode included in the illumination deflector 104, projection deflector 107, and objective lens deflector 110.

[0165] As described above, when the output impedance of the voltage / current control unit 12 and the input impedance of the signal processing unit 302 electrically connected to the electrode are substantially the same, the following effects can be achieved for the connection to each electrode.

[0166] For example, the case where the electron beam mapping apparatus 1 is designed to be in a beam cutoff state when the voltage applied by the voltage / current control unit 12 to a certain electrode of the illumination deflector 104 is outside a certain range will be described. Regarding the connection to this electrode, if the input impedance of the signal processing unit 302A electrically connected to this electrode is substantially the same as the output impedance of the voltage / current control unit 12, the signal processing unit 302A can detect the voltage actually applied to the electrode by discharge. Therefore, when a discharge is detected as described above and the signal processing unit 302A measures that the voltage applied to the electrode by the discharge is outside the aforementioned range, the following prediction can be made: that is, a period during which the electron beam 100 cannot pass through the opening of the second aperture member 105 is predicted, and thus, a reduction in the dose of the electron beam 100 used for mapping is predicted.

[0167] Furthermore, based on the voltage applied to the electrodes of the projection deflector 107 by the voltage / current control unit 12, the shape and size of the electron beam 100 passing through the third aperture member 108 can be known in advance. For the connection to each electrode of the projection deflector 107, when the input impedance of the signal processing unit 302B electrically connected to that electrode is substantially the same as the output impedance of the voltage / current control unit 12, the signal processing unit 302B can detect the voltage actually applied to that electrode by discharge. Therefore, by detecting the discharge as described above, and further, based on the voltage measured by the signal processing unit 302B and also based on the discharge applied to these electrodes, a prediction can be made as follows: that is, the shape and size of the electron beam 100 passing through the third aperture member 108 can be predicted due to the discharge.

[0168] Thus, the predicted effect of discharge on electron beam 100 may also affect the drawing of sample 21 using electron beam 100. Therefore, by comparing with the drawing pattern error, it is possible to identify discharges that are particularly likely to cause drawing pattern errors from the detected discharges.

[0169] <Other Implementation Methods>

[0170] The above describes the case where discharge detection processing is performed during various controls of the electron beam path. The control of the electron beam path is not limited to the above. For example, it is also possible that every other electrode (four electrodes) of the eight electrodes of the projection deflector around the reference line is electrically connected to the voltage / current control unit, and the beam path control unit uses these four electrodes to control the electron beam path. This allows, for example, the simulation of drawing onto the sample. In this case, it is also possible that the remaining four electrodes of the eight electrodes of the projection deflector are connected to the signal processing unit, and discharge detection processing is performed based on the voltage data items corresponding to each of these four electrodes. Alternatively, the electrodes of the objective lens deflector can be used in the same way, either instead of the projection deflector or based on the projection deflector.

[0171] During discharge detection, in order to deflect the electron beam, the coil that alters the magnetic field along the electron beam path does not necessarily have to surround the path of the electron beam. For example, the electron beam can be deflected by altering the magnetic field along the electron beam path using a coil that does not surround the path of the electron beam.

[0172] In the above description, an example was given in which each electrode included in the deflector is electrically connected to the discharge detection unit, and the discharge detection unit performs discharge detection processing based on the potential of the electrode. However, this is not necessarily the case. It is also possible for other electrodes present in the charged particle beam irradiation device to be electrically connected to the discharge detection unit, and for the discharge detection unit to perform discharge detection processing based on the potential of the electrode.

[0173] In this specification, “connection” means electrical connection, including, for example, cases where other components are sandwiched between them.

[0174] In this specification, expressions such as "same," "consistent," "certain," and "maintain" are intended to also include cases where errors exist within the design scope when implementing the technology described in the embodiments. Furthermore, the expression "apply or supply a voltage" is intended to include both the control of applying or supplying the voltage and the actual application or supply of the voltage. Moreover, applying or supplying a voltage may also include applying or supplying, for example, a voltage of 0V.

[0175] Several embodiments have been described above, but these embodiments are merely illustrative and not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, and are also included in the invention described in the technical solution and its equivalents.

Claims

1. A method for detecting discharge sites, used in a charged particle beam irradiation device. The aforementioned charged particle beam irradiation device can switch between a first mode and a second mode. In the first mode described above, by applying voltages to multiple electrodes respectively, the beam of charged particles can be deflected. In the second mode described above, without applying the voltage, data representing the potentials of the plurality of electrodes during the beam emission period can be obtained. In the above-mentioned methods for detecting discharge sites, In the second mode described above, if the change in potential shown in the data related to any one of the plurality of electrodes exceeds a predetermined threshold, a discharge is detected, and the part corresponding to that electrode is detected as the part where a discharge has occurred.

2. The method for detecting discharge sites according to claim 1, wherein, If the potential variation shown in the above data related to two or more of the above electrodes exceeds a predetermined threshold, the region corresponding to the electrode with the largest variation is detected as the region where a discharge has occurred.

3. The method for detecting discharge sites according to claim 1, wherein, If the potential variation shown in the above data related to two or more of the above electrodes exceeds a predetermined threshold, the part corresponding to the electrode with the earliest timing of the peak value of the potential is detected as the part where a discharge has occurred.

4. The method for detecting discharge sites according to claim 1, wherein, When switching from the second mode to the first mode, and the emitted beam is deflected along its path by the change in electric field caused by the voltage applied to the plurality of electrodes or by the change in magnetic field caused by the current flowing through the coil in the charged particle beam irradiation device, data representing the potential of each of the plurality of electrodes is obtained.

5. The method for detecting discharge sites according to claim 1, wherein, When switching from the second mode to the first mode, data representing the potential of each of the multiple electrodes is obtained as the emitted beam passes through the openings of the multiple aperture components provided in the path by means of the electric field change caused by the voltage applied to the multiple electrodes or the magnetic field change caused by the current flowing through the coil provided in the charged particle beam irradiation device.

6. The method for detecting discharge sites according to claim 1, wherein, When switching from the second mode to the first mode, and the emitted beam is irradiated along its path to a position different from the opening of the aperture member provided on the path by means of the electric field change caused by the voltage applied to the plurality of electrodes or the magnetic field change caused by the current flowing in the coil provided in the charged particle beam irradiation device, data representing the potential of each of the plurality of electrodes is obtained.

7. The method for detecting discharge sites according to claim 1, wherein, The first data representing the electric field variation in each vicinity is obtained by multiple detectors in the aforementioned charged particle beam irradiation device. If a discharge is detected, the first data mentioned above and the electrodes related to the detection of the discharge are stored accordingly. Following the aforementioned storage, the multiple detectors acquire second data representing the electric field variations in their respective vicinity. Based on the comparison between the first data and the second data, the discharge generated near the electrode is detected.

8. A discharge site detection device, comprising: Multiple electrodes, based on the voltage applied to each electrode, deflect the beam of charged particles. The signal processing unit acquires data representing the potential of each electrode when the connection destination of the plurality of electrodes is switched from the supply source of the applied voltage; and The control unit detects that a discharge has occurred if the change in potential shown in any of the acquired data exceeds a predetermined threshold, and detects the location corresponding to the electrode associated with the data as the location where a discharge has occurred.

9. The discharge site detection device according to claim 8, wherein, The aforementioned signal processing unit has an input impedance that is substantially the same as the output impedance of the aforementioned voltage supply source.

10. The discharge site detection device according to claim 8, wherein, If the change in potential shown in the data related to two or more of the plurality of electrodes exceeds a predetermined threshold, the control unit will detect the part corresponding to the electrode with the largest change as the part where a discharge has occurred.

11. The discharge site detection device according to claim 8, wherein, When the change in potential shown in the data related to two or more of the plurality of electrodes exceeds a predetermined threshold, the control unit detects the part corresponding to the electrode whose peak value was earliest as the part where a discharge has occurred.

12. The discharge site detection device according to claim 8, wherein, When the connection destination of the aforementioned plurality of electrodes is connected to the supply source for the applied voltage, data representing the potential of each of the aforementioned plurality of electrodes is also obtained when the emitted beam is deflected in its path by the change in electric field caused by the voltage applied to the aforementioned plurality of electrodes or by the change in magnetic field caused by the current flowing through the coil provided in the charged particle beam irradiation device.

13. The discharge site detection device according to claim 8, wherein, When the connection destination of the aforementioned plurality of electrodes is connected to the supply source for the applied voltage, data representing the potential of each of the aforementioned plurality of electrodes is also obtained when the emitted beam passes through the openings of the plurality of aperture components provided in the path by means of the electric field change caused by the voltage applied to the aforementioned plurality of electrodes or the magnetic field change caused by the current flowing through the coil provided in the charged particle beam irradiation device.

14. The discharge site detection device according to claim 8, wherein, When the connection destination of the aforementioned plurality of electrodes is connected to the supply source for the applied voltage, and the emitted beam irradiates a position different from the opening of the aperture member provided on the path by means of the electric field change caused by the voltage applied to the aforementioned plurality of electrodes or the magnetic field change caused by the current flowing in the coil provided in the charged particle beam irradiation device, the data representing the potential of each of the aforementioned plurality of electrodes are also obtained.

15. The discharge site detection device according to claim 8, wherein, The aforementioned control unit is, First data representing the electric field variations in the vicinity is obtained by using multiple detectors. If a discharge is detected, the first data mentioned above and the electrodes related to the detection of the discharge are stored accordingly. After the above storage, the aforementioned multiple detectors acquire second data representing the electric field variations in their respective vicinity. Based on the comparison between the first data and the second data, the discharge generated near the electrode is detected.

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