Electron particle beam imaging device and wafer defect detection method

Abstract

The present application discloses an electron particle beam imaging device and a wafer defect detection method. The electron particle beam imaging device includes an emitting unit, a first converging unit, a second converging unit and two deflection units. The emitting unit is used to emit a particle beam. The first converging unit is arranged downstream of the emitting unit, and the first converging unit is used to converge the particle beam to form a converged beam. The second converging unit is arranged downstream of the first converging unit, and is used to form the converged beam into a fine beam spot. The two deflection units are sequentially arranged downstream of the first converging unit, and each deflection unit is used to change the direction of particle movement. Each deflection unit includes a first deflector responsive to a first excitation source and a second deflector responsive to a second excitation source. The first excitation source and the second excitation source are turned on in opposite states, so that the converged beam emitted by the first converging unit passes through the action of the two first deflectors or the two second deflectors to obtain a scanning beam inclined relative to the surface of the sample to be tested.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor processing technology, and in particular relates to an electron particle beam imaging device and a wafer defect detection method. Background Art

[0002] As the fundamental carrier of chips, wafer quality directly impacts the quality and reliability of subsequent products. In related technologies, wafer defect detection equipment uses an electron microscope to scan the wafer surface and obtain defect-related information based on the scanned image.

[0003] However, the electron microscopes currently in use cannot meet the measurement requirements of wafer edges. On the one hand, this prolongs the defect analysis time and delays the problem-solving cycle; on the other hand, it is not conducive to improving the accuracy of defect detection. Summary of the Invention

[0004] The present invention provides an electron-assisted particle beam imaging device and a wafer defect detection method. The electron-assisted particle beam imaging device utilizes two deflection units to achieve two-stage deflection of the particle beam, thereby scanning the wafer edge. The electron-assisted particle beam imaging device can switch between a first excitation source and a second excitation source to obtain two images, which are combined to determine wafer defects, improving the accuracy of wafer defect detection.

[0005] In a first aspect, an embodiment of the present application provides an imaging device with an electron particle beam, comprising an emitting unit, a first converging unit, a second converging unit, and two deflection units, wherein the emitting unit is configured to emit a particle beam; the first converging unit is disposed downstream of the emitting unit, and is configured to converge the particle beam to form a converged beam; the second converging unit is disposed downstream of the first converging unit, and is configured to form the converged beam into a fine beam spot; the two deflection units are sequentially disposed downstream of the first converging unit, each deflection unit is configured to change a moving direction of particles, and each deflection unit comprises a first deflector responsive to a first excitation source and a second deflector responsive to a second excitation source;

[0006] The first excitation source and the second excitation source are turned on in opposite states, so that the focused beam emitted by the first converging unit passes through the two first deflectors or the two second deflectors to obtain a scanning beam inclined relative to the surface of the sample to be tested.

[0007] In some embodiments, the first excitation source is a voltage excitation source, the second excitation source is a current excitation source, and in each deflection unit, the first deflector is an electrostatic deflector, and the second deflector is a magnetoelectric deflector.

[0008] In some embodiments, in each deflection unit, along the radial direction of the particle beam, the first deflector is arranged on the inner side of the second deflector.

[0009] In some embodiments, in each deflection unit, the first deflector includes at least one pair of parallel pole plates, and the second deflector includes two coils connected to one pair of pole plates, and the coils are arranged on opposite sides of the pole plates.

[0010] In some embodiments, in each deflection unit, a field of view angle corresponding to the first deflector is smaller than a field of view angle corresponding to the second deflector.

[0011] In some embodiments, in the two deflection units, the maximum field of view corresponding to the first deflector is smaller than the minimum field of view corresponding to the second deflector.

[0012] In some embodiments, along the radial direction of the particle beam, the two deflection units are both disposed inside the second converging unit, so that the scanning beam is deflected while being converged.

[0013] In some of the embodiments, the first converging unit includes at least one converging lens, which is an electromagnetic lens or an electrostatic lens;

[0014] The second converging unit includes at least an objective lens.

[0015] In a second aspect, an embodiment of the present application provides a wafer defect detection method, which is implemented based on the electron particle beam imaging device provided in any of the aforementioned embodiments. The wafer defect detection method includes:

[0016] Turning on a first excitation source to obtain a first detection image of a first side of a wafer to be tested;

[0017] Turn off the first excitation source, turn on the second excitation source, and acquire a second detection image of the first side of the wafer to be tested;

[0018] The defect type is determined based on the first detection image and the second detection image.

[0019] In some embodiments, the wafer defect detection method further includes: acquiring a second detection image of the first side of the wafer to be detected based on the first detection image; and / or,

[0020] A second inspection image of the first side of the wafer to be measured is acquired based on at least one of a radius and an angle of the wafer to be measured.

[0021] The electron-assisted particle beam imaging device of the embodiment of the present application gathers particles emitted from the emission unit through a first converging unit to form a particle beam, and implements two-stage deflection of the particle beam through two deflection units arranged downstream of the first converging unit. At the same time, the second converging unit focuses the particle beam to form a fine beam spot. The deflected scanning particle beam can move relative to the wafer surface to detect defects on the wafer surface. The electron-assisted particle beam imaging device can adjust the deflection amplitude of the scanning particle beam through two first deflectors or two second deflectors, thereby obtaining two images with different fields of view, which can provide more image basis for wafer surface defect determination. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0023] Figure 1 A schematic diagram of a system with an electron particle beam imaging device according to some embodiments of the present application;

[0024] Figure 2 A schematic flow chart of a wafer defect detection method according to some embodiments of the present application;

[0025] Figure 3 A schematic flow chart of a wafer defect detection method according to some embodiments of the present application;

[0026] Figure 4 Schematic diagram of a sub-process of a wafer defect detection method according to some embodiments of the present application.

[0027] The accompanying drawings in the specific implementation manner are as follows:

[0028] 100, particle beam; 110, electron source; 121, first electrode; 122, second electrode;

[0029] 200, first converging unit; 210, condenser lens;

[0030] 300, second converging unit;

[0031] 400, deflection unit; 410, first deflector; 420, second deflector. DETAILED DESCRIPTION

[0032] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0034] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0035] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0036] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0037] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0038] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0039] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0040] As the fundamental carrier of chips, wafer quality directly impacts the quality and reliability of subsequent products. In related technologies, wafer defect detection equipment uses an electron microscope to scan the wafer surface and obtain defect-related information based on the scanned image.

[0041] However, although the currently used scanning electron microscope (SEM) has high resolution, it cannot simultaneously scan the top bevel and bevel areas of the wafer surface. Therefore, when part of the defect is located in the edge area of ​​the wafer, the electron microscope cannot fully observe the defect, making it difficult to meet measurement requirements. This not only prolongs the defect analysis time and delays the problem solving cycle, but also easily leads to misjudgment and other situations.

[0042] In addition, when the relevant electron particle beam imaging device scans and images the wafer surface, due to the small field of view of the image, it is difficult to clearly observe whether there are pits or protrusions at the defect site in the same image, which is not conducive to improving the accuracy of defect detection.

[0043] In order to solve the problems in the prior art, the embodiments of the present application provide an electron particle beam imaging device and a wafer defect detection method. The electron particle beam imaging device provided in the embodiments of the present application is first introduced below.

[0044] See also Figure 1In a first aspect, an embodiment of the present application provides an electron particle beam imaging device for acquiring an image of a surface to be measured on a wafer. The electron particle beam imaging device includes an emitting unit, a first converging unit 200 disposed downstream of the emitting unit, a second converging unit 300 disposed downstream of the first converging unit 200, and two deflection units 400. The emitting unit is used to emit a particle beam 100, the first converging unit 200 is used to converge the particle beam 100 to form a converged beam, the second converging unit 300 is used to form the converged beam into a fine beam spot, and each deflection unit 400 is used to change the direction of particle movement. Each deflection unit 400 includes a first deflector 410 and a second deflector 420. The first deflector 410 responds to a first excitation source, and the second deflector 420 responds to a second excitation source. The first excitation source and the second excitation source have opposite turning states.

[0045] The particle beam 100 emitted by the emission unit undergoes a first convergence through the first converging unit 200 to form a concentrated beam, and the concentrated beam undergoes a second convergence through the second converging unit 300 to form a fine beam spot. The fine beam spot changes its moving direction under the action of the two deflection units 400, and finally forms a scanning beam that is inclined relative to the surface of the sample to be tested.

[0046] Thus, by controlling the deflection unit 400, the inclination angle of the scanning beam relative to the sample surface to be tested can be adjusted, and then the scanning beam can be moved relative to the sample to traverse the surface to be tested, thereby obtaining an image for defect detection. The electron particle beam imaging device can activate the two first deflectors 410 or the two second deflectors 420 by switching the first excitation source or the second excitation source, adjust the deflection amplitude of the particles to adjust the exit angle of the scanning beam, and thus obtain two images with different fields of view. The two images can be used to observe the microscopic and macroscopic morphologies of defects respectively, providing more image basis for wafer defect detection and judgment, and helping to improve the accuracy and efficiency of wafer defect detection.

[0047] It should be noted that the microscopic morphology and macroscopic morphology referred to in this application are different from the microscopic and macroscopic in a broad sense, but refer to the relative microscopic in which defect details can be observed, and the relative macroscopic in which most defect boundary lines or the entire defect boundary lines can be observed.

[0048] According to some embodiments of the present application, the first excitation source is a voltage excitation source, and the first deflector is an electrostatic deflector.

[0049] Optionally, the first deflector 410 is configured as a plate-type electrostatic deflector.

[0050] Optionally, the first deflector 410 is configured as a column-type electrostatic deflector. Exemplarily, the first deflector 410 is an octupole electrostatic deflector.

[0051] Thus, the first deflector 410 generates an electrostatic field under voltage excitation. Particles entering the field are deflected by the electrostatic force, thereby deflecting the exit direction of the fine beam spot. Adjusting the excitation voltage can change the electrostatic force exerted on particles entering the field, thereby adjusting the exit direction of the fine beam spot.

[0052] It can be understood that, in the two deflection units 400, the electric field strength of the first deflector 410 close to the sample is greater than the electric field strength of the first deflector 410 away from the sample, so that the focused beam can be further deflected under the action of the electrostatic force when entering the first deflector 410 close to the sample. The deflection angle of the scanning beam is expanded through two-stage deflection. Combined with the high-speed scanning characteristics of electrostatic deflection, the efficiency of the electron particle beam imaging device in obtaining the image of the sample surface to be tested is improved.

[0053] According to some embodiments of the present application, the second excitation source is a current excitation source, and the second deflector 420 is a magnetoelectric deflector.

[0054] Thus, the second deflector 420 generates a magnetic field under current excitation. Particles entering the field are deflected by the Lorentz force, thereby deflecting the exit direction of the fine beam spot. Adjusting the excitation current can change the Lorentz force exerted on particles entering the magnetic field, thereby adjusting the exit direction of the fine beam spot.

[0055] It can be understood that, in the two deflection units 400, the magnetic field strength of the second deflector 420 close to the sample is greater than the magnetic field strength of the second deflector 420 away from the sample, so that when the focused beam enters the second deflector 420 close to the sample, it can be further deflected under the action of the Lorentz force. The deflection angle of the scanning beam is expanded through two-stage deflection, thereby realizing scanning imaging of the edge position of the wafer surface to be measured and measuring the edge position of the wafer.

[0056] Thus, the electron-assisted particle beam imaging device can achieve two-stage electrostatic deflection of the particle beam 100 through two electrostatic deflectors, or two-stage magnetic deflection of the particle beam 100 through two magnetic deflectors, thereby obtaining two types of images with different fields of view for combined determination of wafer defect types. Furthermore, the electron-assisted particle beam imaging device can also adjust the deflection unit 400 by switching between the first and second excitation sources as needed, using magnetic deflectors to obtain images with smaller differences, or using electrostatic deflectors to scan the wafer at high speed to obtain inspection images more quickly, flexibly adapting to different inspection requirements.

[0057] According to certain embodiments of the present application, in the same deflection unit 400 , the first deflector 410 and the second deflector 420 are arranged sequentially along the emission direction of the particle beam 100 , or, along the radial direction of the particle beam 100 , the first deflector 410 is arranged on the inner side or the outer side of the second deflector 420 .

[0058] Furthermore, in the two deflection units 400 , the positional relationship between the first deflector 410 and the second deflector 420 is the same, or the positional relationship between the first deflector 410 and the second deflector 420 is different.

[0059] Therefore, the internal structure of the deflection unit 400 can be flexibly adjusted according to different production requirements such as imaging accuracy or equipment space.

[0060] For example, see Figure 1 In each deflection unit 400, the first deflector 410 is positioned inwardly of the second deflector 420 along the radial direction of the particle beam 100. This shortens the exit path of the particle beam 100, alleviating the degradation of beam spot quality caused by an excessively long path. Furthermore, the integration of the first deflector 410 and the second deflector 420 along the exit direction of the particle beam 100 helps reduce the size of the electron-bearing particle beam imaging device, achieving miniaturization of the detection equipment.

[0061] According to certain embodiments of the present application, in each deflection unit 400, the first deflector 410 includes at least one pair of parallel plates, and the second deflector 420 includes two coils, each of which is disposed corresponding to one of the pairs of plates. For example, the coils of the second deflector 420 are disposed on opposite sides of the plates, that is, outside the plates in the radial direction of the particle beam 100.

[0062] Further optionally, in some embodiments, the first deflector 410 is directly connected to the second deflector 420 to achieve relative fixation of the first deflector 410 and the second deflector 420 .

[0063] Further optionally, in some other embodiments, the deflection unit 400 further includes a connecting member, and the first deflector 410 and the second deflector 420 are both mounted on the connecting member to achieve relative fixation of the first deflector 410 and the second deflector 420 .

[0064] According to certain embodiments of the present application, in each deflection unit 400 , the field of view angle corresponding to the first deflector 410 is smaller than the field of view angle corresponding to the second deflector 420 .

[0065] Therefore, the electron particle beam imaging device can obtain two images with different field of view ranges by turning on the first excitation source or the second excitation source, and then obtain more defect morphology information through image comparison, providing more basis for defect judgment, and realizing the improvement of defect detection operation efficiency and operation accuracy.

[0066] Furthermore, in the two deflection units 400 , the maximum field of view angle corresponding to the first deflector 410 is smaller than the minimum field of view angle corresponding to the second deflector 420 .

[0067] As a result, the image obtained by turning on the first excitation source is significantly different from the image obtained by turning on the second excitation source, thereby achieving the acquisition of macroscopic and microscopic morphological information of the defect, and further improving the accuracy of the defect detection operation.

[0068] According to some embodiments of the present application, the deflection unit 400 away from the sample is disposed inside the second converging unit 300 along the radial direction of the particle beam 100 .

[0069] Optionally, along the radial direction of the particle beam 100 , the deflection unit 400 close to the sample is also provided in the second converging unit 300 , so that the focused beam can complete two-stage deflection inside the second converging unit 300 , thereby improving the accuracy of the scanning beam.

[0070] As a result, the integration level of the electron-bearing particle beam imaging device is improved while the emission path of the particle beam 100 is shortened, thereby alleviating the degradation of the beam spot quality caused by the excessively long path of the particle beam 100; in addition, the electrostatic field or magnetic field of the deflection unit 400 can be superimposed on the field distribution formed by the second converging unit 300, thereby reducing deflection chromatic aberration and compensating for the loss of imaging accuracy caused by the two-stage deflection setting.

[0071] According to some embodiments of the present application, the emission unit includes an electron source 110 to excite an electron beam, and an electron particle beam imaging device performs electron beam imaging to achieve wafer defect detection.

[0072] Optionally, the emission unit further includes a first electrode 121, which is disposed downstream of the electron source 110. The voltage V1 of the first electrode 121 is less than 0. The first electrode 121 is used to suppress stray electrons in the electron beam to adjust the current size, thereby adjusting the energy size of the electron beam.

[0073] Further optionally, the emission unit also includes a second electrode 122, which is arranged downstream of the electron source 110, and the voltage V2 of the second electrode 122 is greater than or equal to 0. The second electrode 122 is used to guide the movement path of the electron beam and reduce energy loss. The electron beam can be shaped by adjusting the size of V2.

[0074] Further optionally, the electron source 110, the first electrode 121, and the second electrode 122 are coaxially arranged in sequence, and the high point tail difference between the first electrode 121 and the second electrode 122 can accelerate the electrons, thereby adjusting the energy of the electron beam emitted by the emission unit so that it is sufficient to be recognized by the detector in subsequent detection.

[0075] It can be understood that in some embodiments, the emission unit includes an ion source, the particle beam 100 is an ion beam, the ion beam can be deflected in response to an electrostatic deflector or a magnetic deflector, and a structure for adjusting the ion beam quality is correspondingly provided downstream of the ion source.

[0076] According to some embodiments of the present application, the first converging unit 200 includes at least one converging lens 210 .

[0077] Optionally, the first converging unit 200 is provided with two condensing mirrors 210 , and along the electron beam emission direction, the two condensing mirrors 210 are both located upstream of the second converging unit 300 and any deflection unit 400 .

[0078] Optionally, the condenser mirror 210 is configured as at least one of an electromagnetic lens and an electrostatic lens to achieve a focusing effect on the electron beam. Exemplarily, the two condenser mirrors 210 include an electromagnetic lens and a classical lens.

[0079] Therefore, by adjusting the field distribution of the condensing mirror 210, the focusing effect of the first converging unit 200 on the electron beam is adjusted, thereby achieving beam diameter adjustment or energy adjustment of the concentrated beam.

[0080] According to some embodiments of the present application, the second converging unit 300 includes at least an objective lens.

[0081] Optionally, the second converging unit 300 is configured as a separate objective lens, and along the emission direction of the particle beam, the two deflection units are both located inside the objective lens.

[0082] Optionally, the second converging unit 300 further includes at least one lens, which is an electromagnetic lens or an electrostatic lens, to enhance the focusing effect of the second converging unit on the particle beam. Specifically, along the emission direction of the particle beam, the lens is disposed upstream of the objective lens.

[0083] See also Figure 2 In a second aspect, an embodiment of the present application further provides a wafer defect detection method, which is implemented based on the electron particle beam imaging device provided in any of the aforementioned embodiments. The wafer defect detection method includes:

[0084] S100, turning on a first excitation source to obtain a first detection image of a first side of a wafer to be tested;

[0085] S200, turning off the first excitation source, turning on the second excitation source, and acquiring a second detection image of the first side of the wafer to be tested;

[0086] S300 , determining the defect type based on the first detection image and the second detection image.

[0087] Therefore, the first detection image and the second detection image can complement each other and be combined to realize defect determination of the wafer surface to be tested, thereby improving the accuracy of wafer defect detection.

[0088] It should be noted that the wafer to be tested may be a bare wafer or a processed wafer, such as a patterned wafer. When the wafer to be tested is a processed wafer, the first side is the processed side of the processed wafer.

[0089] According to certain embodiments of the present application, the wafer defect detection method further includes:

[0090] S010: Calibrate the wafer to be measured based on at least one of the notch mark and the edge mark of the wafer to be measured to obtain the center position of the wafer to be measured.

[0091] Exemplarily, the wafer to be measured is calibrated based on the notch mark and the edge mark of the wafer to be measured to improve positioning accuracy.

[0092] Thus, the spatial position of the wafer to be measured is obtained, and the electron particle beam imaging device moves according to the center position of the wafer to be measured so that the fine beam spot is projected toward the center of the wafer to be measured when the deflection unit 400 is not turned on.

[0093] According to some embodiments of the present application, step S200 specifically includes:

[0094] S210A, acquiring a second detection image of the first side of the wafer to be tested based on the first detection image;

[0095] S210B, acquiring a second detection image of the first side of the wafer to be measured based on at least one of a radius and an angle of the wafer to be measured.

[0096] Specifically, the above steps S210A and S210B can be performed separately or together. When step S210A and step S210B are performed together, the execution order of the two steps is not limited. For example, please refer to Figure 3 When steps S210A and S210B are executed together, the latter step can further obtain a second detection sub-image in the second detection image obtained by the former step, and determine the defect type by combining the second detection sub-image with the first detection image.

[0097] Therefore, the target position and the deflection angle of the scanning beam are determined through the first detection image / the radius of the wafer to be measured / the angle of the wafer to be measured, and the second detection image is obtained, thereby improving the efficiency of wafer defect detection operations.

[0098] See also Figure 4 According to some embodiments of the present application, step S300 includes:

[0099] S310, identifying a first detection image and obtaining first defect classification information;

[0100] S320: Acquire a standard image set based on the first defect classification information, compare the second inspection image with the standard image set, and acquire second defect classification information.

[0101] Thus, defects are identified through the first detection image to achieve pre-classification. For defects that are difficult to determine based on the first detection image, the possible defects can be quickly identified, shortening the problem-solving cycle.

[0102] Furthermore, according to some embodiments of the present application, step S300 further includes:

[0103] S330: When the second defect classification information contains two or more defects, collect elemental components at the defect to determine the defect type.

[0104] Optionally, the elemental composition of the defect is determined by energy dispersive X-ray spectroscopy.

[0105] Therefore, for defects that are still difficult to determine by combining the first detection image and the second detection image, element composition analysis is used to further eliminate them and determine the defect type.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An electron particle beam imaging device, characterized in that: include: a launching unit, for launching a particle beam; a first converging unit, disposed downstream of the emitting unit, for converging the particle beam to form a concentrated beam; a second converging unit, disposed downstream of the first converging unit, for forming the focused beam into a fine beam spot; two deflection units, sequentially disposed downstream of the first converging unit, each of the deflection units being used to change a moving direction of particles, and each of the deflection units comprising a first deflector responsive to a first excitation source and a second deflector responsive to a second excitation source; The first excitation source and the second excitation source are turned on in opposite states, so that the focused beam emitted by the first converging unit passes through the two first deflectors or the two second deflectors to obtain a scanning beam inclined relative to the surface of the sample to be tested.

2. The electron particle beam imaging device according to claim 1, characterized in that The first excitation source is a voltage excitation source, the second excitation source is a current excitation source, and in each of the deflection units, the first deflector is an electrostatic deflector, and the second deflector is a magnetoelectric deflector.

3. The electron particle beam imaging device according to claim 2, characterized in that: In each of the deflection units, along the radial direction of the particle beam, the first deflector is arranged on the inner side of the second deflector.

4. The electron particle beam imaging device according to claim 3, characterized in that: In each of the deflection units, the first deflector includes at least one pair of mutually parallel pole plates, and the second deflector includes two coils. The two coils are connected to one pair of pole plates, and the coils are arranged on opposite sides of the pole plates.

5. The electron particle beam imaging device according to claim 2, characterized in that: In each of the deflection units, a field of view angle corresponding to the first deflector is smaller than a field of view angle corresponding to the second deflector.

6. The electron particle beam imaging device according to claim 5, characterized in that: In the two deflection units, the maximum field of view angle corresponding to the first deflector is smaller than the minimum field of view angle corresponding to the second deflector.

7. The electron particle beam imaging device according to claim 1, characterized in that: Along the radial direction of the particle beam, the two deflection units are both arranged inside the second converging unit, so that the scanning beam is deflected while being converged.

8. The electron particle beam imaging device according to claim 1, characterized in that: The first converging unit includes at least one condensing lens, and the condensing lens is an electromagnetic lens or an electrostatic lens; The second converging unit includes at least an objective lens.

9. A wafer defect detection method, implemented based on the electron particle beam imaging device according to any one of claims 1 to 8, characterized in that: include: Turning on a first excitation source to obtain a first detection image of a first side of a wafer to be tested; Turn off the first excitation source, turn on the second excitation source, and acquire a second detection image of the first side of the wafer to be tested; The defect type is determined based on the first detection image and the second detection image.

10. The wafer defect detection method according to claim 9, wherein: Also includes: Acquire a second detection image of the first side of the wafer to be tested based on the first detection image; and / or, A second inspection image of the first side of the wafer to be measured is acquired based on at least one of a radius and an angle of the wafer to be measured.

Images