Shaping aperture set for multi-beam array configuration

Abstract

An aperture array for a multi-beam array system and a method for selecting a subset of beams from a multi-beam array system are provided. The aperture array includes an array body disposed proximate to a beam source. The array body includes a plurality of apertures, at least two of the apertures having different geometries. The array body is movable relative to an optical axis of the beam source via an actuator such that a subset of beams from the beam source is selected based on the geometry of the apertures that intersect the optical axis.

Description

Technical Field

[0001] The present disclosure relates to a multi-beam array system, and more particularly to an aperture array for a multi-beam array system.

Background Art

[0002] The evolution of the semiconductor manufacturing industry has placed greater demands on yield management, particularly in metrology and inspection systems. Although critical dimensions continue to shrink, the industry needs to reduce the time to achieve high yields and high-value production. Minimizing the total time from detecting a yield problem to fixing it determines the return on investment for semiconductor manufacturers.

[0003] Manufacturing semiconductor devices such as logic devices and memory devices typically involves processing semiconductor wafers using a number of manufacturing processes to form various features and multiple levels of the semiconductor device. For example, lithography is a semiconductor manufacturing process that involves transferring a pattern from a reticle to a photoresist disposed on a semiconductor wafer. Further examples of semiconductor manufacturing processes include, but are not limited to, chemical mechanical polishing (CMP), etching, deposition, and ion implantation. Multiple semiconductor devices can be manufactured on a single semiconductor wafer that is separated into individual semiconductor devices.

[0004] The inspection process is used at various steps during semiconductor manufacturing to detect defects on a wafer in order to promote higher yields in the manufacturing process and thus higher profits. Inspection is always an important part in manufacturing semiconductor devices such as integrated circuits (ICs). However, as the dimensions of semiconductor devices decrease, inspection becomes even more important for the successful manufacture of acceptable semiconductor devices because smaller defects can cause device failures. For example, as the dimensions of semiconductor devices shrink, even relatively small defects can cause undesirable aberrations in semiconductor devices, so detection of defects of reduced size is required.

[0005] One device used in the inspection process is a multi-beam array. The multi-beam array emits a plurality of electron beams over an area of a semiconductor device. During the inspection process, it may be desirable to select only a subset of the electron beams. For example, a certain array shape may be required for different inspection processes, or a different array shape may provide a higher resolution image. In a typical inspection system, changing a subset of electron beams may require replacing individual blankers placed in the optical path of the multi-beam array or using a processor to control individual electron beams to be turned on or off. These methods can add cost to the inspection system and / or require additional maintenance.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] Accordingly, there is a need for new methods and devices for selecting a subset of a multi-beam array. These new methods and devices reduce downtime during the inspection process, add minimal cost to the inspection system, and require little maintenance.

Means for Solving the Problems

[0008] Embodiments of the present disclosure provide an aperture array for a multi-beam array system. The aperture array may include an array body disposed close to the beam source. The array body may include a plurality of apertures (openings). At least two of the apertures may have different geometries. The array body may be movable relative to the optical axis of the beam source via an actuator such that a subset of the beams from the beam source can be selected based on the geometry of the aperture that intersects the optical axis.

[0009] According to an embodiment of the present disclosure, at least one of the plurality of apertures may be circular.

[0010] According to an embodiment of the present disclosure, at least one of the plurality of apertures may be rectangular.

[0011] According to an embodiment of the present disclosure, at least one of the plurality of apertures may be hexagonal.

[0012] According to an embodiment of the present disclosure, two of the plurality of apertures may have different sizes and the same shape.

[0013] According to an embodiment of the present disclosure, the plurality of apertures may be arranged one-dimensionally within the array body.

[0014] According to an embodiment of the present disclosure, the actuator may include a linear actuator configured to move the array body in the X direction relative to the optical axis of the beam source. The X direction may be perpendicular to the optical axis.

[0015] According to an embodiment of the present disclosure, the actuator may include a rotary actuator configured to rotate the array body about a rotation axis with respect to the optical axis of the beam source. The rotation axis may be parallel to the optical axis.

[0016] According to an embodiment of the present disclosure, the plurality of apertures may be two-dimensionally arranged within the array body.

[0017] According to an embodiment of the present disclosure, the actuator may include a pair of linear actuators configured to move the array body in the X direction and the Y direction, respectively, with respect to the optical axis of the beam source. The X direction and the Y direction may be perpendicular to the optical axis and may be perpendicular to each other.

[0018] According to an embodiment of the present disclosure, the array body may be composed of aluminum nitride, polycrystalline diamond, graphite, molybdenum, or tungsten.

[0019] According to an embodiment of the present disclosure, the aperture array may further include a heat dissipation device disposed on the array body. The heat dissipation device may be configured to actively or passively dissipate heat from the array body.

[0020] According to an embodiment of the present disclosure, the distance between the array body and the beam source may be 10 cm to 20 cm.

[0021] According to an embodiment of the present disclosure, the beam source may be an electron beam source.

[0022] Embodiments of the present disclosure provide a method for selecting a subset of beams from a multi-beam array system. The method may include providing an array body in proximity to a beam source. The array body may include a plurality of apertures. At least two of the apertures may have different geometric shapes. The method may further include moving the array body relative to the optical axis of the beam source via an actuator such that one of the apertures can intersect the optical axis. The method may further include generating an electron beam around the optical axis using the beam source. The method may further include directing the electron beam through the array body to select a subset of the electron beam based on the shape of the aperture that intersects the optical axis.

[0023] According to embodiments of the present disclosure, at least one of the plurality of apertures may be circular. When the aperture that intersects the optical axis is circular, the method may further include performing a hot spot inspection operation on a portion of the wafer located within the optical axis downstream of the array body.

[0024] According to embodiments of the present disclosure, at least one of the plurality of apertures may be rectangular. When the aperture that intersects the optical axis is rectangular, the method may further include performing a swath operation on a portion of the wafer located within the optical axis downstream of the array body.

[0025] According to one embodiment of the present disclosure, at least one of the plurality of apertures may be hexagonal. When the aperture that intersects the optical axis is hexagonal, the method may further include performing a step and settle operation on a portion of the wafer located within the optical axis downstream of the array body.

[0026] According to an embodiment of the present disclosure, the method further includes moving the array body relative to the optical axis of the beam source via an actuator such that different apertures among the apertures intersect the optical axis. The method may further include directing an electron beam through the array body to select different subsets of the electron beam based on the shape of different apertures among the apertures that intersect the optical axis.

[0027] According to an embodiment of the present disclosure, the distance between the array body and the beam source can be 10 cm to 20 cm.

Brief Description of the Drawings

[0028] To more fully understand the nature and object of the present disclosure, please refer to the following detailed description in conjunction with the accompanying drawings.

Figure 1A

Figure 1B

Figure 2A

Figure 2B

Figure 3A

Figure 3B

Figure 3C

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0029] The claimed subject matter is described with respect to certain embodiments, and other embodiments, including those that do not provide all of the benefits and features described herein, are also within the scope of the present disclosure. Various structural, logical, process step, and electronic changes can be made without departing from the scope of the present disclosure. Accordingly, the scope of the present disclosure is defined only by reference to the appended claims.

[0030] As shown in FIG. 1A, an embodiment of the present disclosure provides an aperture array 100 for a multi-beam array system. The aperture array 100 can include an array body 10. The array body 10 can be a plate having a thickness of at least 100 μm. The array body 10 may be composed of one of the following materials: aluminum nitride, polycrystalline diamond, graphite, molybdenum, and tungsten. Other materials are possible, and these materials are listed only as examples.

[0031] The array body 10 may include a plurality of apertures 12. The array body 10 may be machined to define a plurality of apertures 12. For example, a laser cutting operation can be used to define a plurality of apertures 12 in the array body 10. Other operations, such as electrical discharge machining (EDM), etching, or any other suitable operation, can be used to define a plurality of apertures 12 within the array body 10. At least two of the plurality of apertures 12 may have different geometries. For example, each of the plurality of apertures 12 may have a different size or a different shape. Each of the plurality of apertures 12 may have a size ranging from 1 mm to 25 mm. Each of the plurality of apertures 12 may be suitable for a particular operation of the multi-beam array system. The aperture 12 can clip or block a portion of the electron beam.

[0032] According to an embodiment of the present disclosure, at least one of the plurality of apertures 12 may be circular. For example, as shown in FIGS. 1A, 2A, and 3A, the plurality of apertures 12 may include a circular aperture 12a. The circular aperture 12a may be suitable for hot spot inspection operations. A hot spot is a feature on a semiconductor device or wafer that is susceptible to pattern failures. Further details of hot spot inspection are known in the relevant art and will not be elaborated here.

[0033] According to an embodiment of the present disclosure, at least one of the plurality of apertures 12 may be rectangular. For example, as shown in FIGS. 1A, 2A, and 3A, the plurality of apertures 12 may include a rectangular aperture 12b. The rectangular aperture portion 12b may have an aspect ratio of 1:1 to 2:1. The rectangular aperture 12b is suitable for swath operations. A swath can take a series of images or scan across a row of a semiconductor device or a portion of a wafer. For example, the wafer may move while imaging occurs such that a strip (swath) of a two-dimensional image is generated. This process can be repeated using a plurality of such swaths until the entire area of interest is imaged. Further details of the swath operation are known in the relevant art and will not be elaborated here.

[0034] According to an embodiment of the present disclosure, at least one of the plurality of apertures 12 may be hexagonal. For example, as shown in FIGS. 1A, 2A, and 3A, the plurality of apertures 12 may include a hexagonal aperture 12c. The hexagonal aperture portion 12c may be suitable for step and settle operations. The wafer can be stationary to capture an image of the wafer at a certain position, but the wafer can move between various imaging positions. This movement and imaging process can be repeated during the step and settle operation until the entire area of interest is imaged. Further details of the step and settle operation are known in the relevant art and will not be elaborated here.

[0035] According to an embodiment of the present disclosure, two of the plurality of apertures 12 can have the same shape but different sizes. The smaller-sized aperture can provide a higher resolution for operations corresponding to the aperture shape. For example, as shown in FIGS. 1A, 2A, and 3A, the plurality of apertures 12 can include a first hexagonal aperture 12c and a second hexagonal aperture 12d. The second hexagonal aperture 12d can provide a higher resolution step and centering operation as compared to the first hexagonal aperture 12c.

[0036] The array body 10 may be disposed close to a beam source in a multi-beam array system. The distance between the array body and the beam source may depend on the design of the system. For example, the array body may be disposed within 10 cm to 20 cm from the beam source. The beam source may be an electron beam source. The beam source may include a single beam or may be a multi-beam array configured to emit multi-beams. The beam source may define an optical axis such that the energy from the beam source is directed towards the wafer. The array body 10 may be disposed upstream of any focusing element in the multi-beam array system. By arranging the array body 10 such that one of the plurality of apertures 12 intersects the optical axis of the beam source, unwanted beams from the beam source can be clipped by the array body 10 and prevented from being directed towards the wafer. Accordingly, a subset of the beams from the beam source can be selected based on the geometric shape of the aperture 12 that intersects the optical axis. For example, the aperture 12 may coincide with the optical axis. It can be understood that optimizing the distance between the array body 10 and the beam source can provide the following advantages. (1) There is less Coulomb effect on the electron beam. (2) Less power is required to move the beam optics (since some of the electron beams are clipped). (3) Less heat is generated using the electron beam (because the beam current is low after some of the electron beams are clipped).

[0037] The array body 10 may be movable relative to the optical axis of the beam source. By moving the array body 10, the optical axis may intersect a different one of the plurality of apertures 12. Thus, different subsets of the beam may be selected based on the different geometries of the different apertures that intersect the optical axis.

[0038] According to an embodiment of the present disclosure, the plurality of apertures 12 may be arranged one-dimensionally within the array body 10. For example, as shown in FIG. 1A, the plurality of apertures 12 may be arranged linearly such that the center points of each of the apertures 12 are collinear. In this way, the array body 10 can be moved along a single axis perpendicular to the optical axis to change which aperture 12 intersects the optical axis. For example, as shown in FIG. 1B, the hexagonal aperture portion 12c is currently selected because it coincides with the optical axis. By moving the array body in the X direction (left or right in FIG. 1B), a different aperture (e.g., the rectangular aperture portion 12b or the second hexagonal aperture portion 12d) can be selected.

[0039] According to an embodiment of the present disclosure, the aperture array 100 may include a linear actuator 14x. As shown in FIG. 1A, the linear actuator 14x may be configured to move the array body 10 in the X direction relative to the optical axis of the beam source. The X direction may be perpendicular to the optical axis. In this way, the linear actuator 14x can move the array body 10 along a single axis to change which aperture 12 intersects the optical axis.

[0040] Alternatively, as shown in FIG. 2A, the plurality of apertures 12 may be arranged in a circular shape such that the center point of each aperture 12 forms an annular shape. In this way, the array body 10 can rotate around a single axis parallel to the optical axis to change which aperture 12 intersects the optical axis. For example, as shown in FIG. 2B, the hexagonal aperture portion 12c is currently selected because it coincides with the optical axis. A different aperture (e.g., the rectangular aperture 12b) can be selected by rotating the array body 180 degrees around the rotation axis. Similarly, the circular aperture 12a or the second hexagonal aperture 12d can be selected by rotating the array body 10 90 degrees and -90 degrees around the rotation axis, respectively.

[0041] According to an embodiment of the present disclosure, the aperture array 100 can include a rotation actuator 14r. As shown in FIGS. 2A and 2B, the rotation actuator 14r may be configured to rotate the array body 10 in a circumferential direction around the rotation axis. The rotation axis may be perpendicular to the array body 10 and parallel to the optical axis. The center points of the plurality of apertures 12 may be at the same distance from the rotation axis. In this way, the rotation actuator 14r can rotate the array body 10 to change which aperture 12 intersects the optical axis.

[0042] According to an embodiment of the present disclosure, the plurality of apertures 12 may be two-dimensionally arranged within the array body 10. For example, as shown in FIG. 3A, the plurality of apertures 10 may be arranged in a grid such that the center point of each aperture 12 corresponds to an X-Y position on the grid. In this way, the array body 10 can move along two axes each perpendicular to the optical axis, and which aperture 12 intersects the optical axis can be changed according to the X-Y position of each aperture 12.

[0043] According to an embodiment of the present disclosure, the aperture array 100 can include a pair of linear actuators 14x, 14y. As shown in FIG. 3A, the pair of linear actuators 14x, 14y may be configured to move the array body 10 in the X direction and the Y direction, respectively, with respect to the optical axis of the light source. For example, one linear actuator 14x may move the array body 10 in the X direction, and the other linear actuator 14y may move the array body 10 in the Y direction. The X direction and the Y direction may be perpendicular to the optical axis and may be perpendicular to each other. In this way, by moving the array body 10 along two axes, it is possible to change which aperture 12 intersects the optical axis according to the X-Y position of each aperture 12. For example, as shown in FIG. 3B, the hexagonal aperture portion 12c coincides with the optical axis and is currently selected. A different aperture (e.g., the second hexagonal aperture 12d) can be selected by moving the array body in the X direction (to the right in FIG. 3B). Further, as shown in FIG. 3C, a different aperture (e.g., the circular aperture 12a) can be selected by moving the array body in the Y direction (to the left in FIG. 3C). Similarly, different apertures (e.g., the rectangular aperture 12b) may be selected by moving the array body along the X direction and the Y direction.

[0044] According to an embodiment of the present disclosure, the aperture array 100 may include a heat dissipation device 20 disposed on the array body 10. The heat dissipation device 20 may be disposed on the upper side, the lower side, or both sides of the array body 10. Due to the heat generated by the beam source, the array body 10 may be exposed to high heat. In order to prevent damage to the array body 10, it may be desirable to dissipate heat from the array body 10 and maintain the temperature of the array body 10 below 10°C. The heat dissipation device 20 may be configured to actively or passively dissipate heat from the array body 10. For example, as shown in FIGS. 1 to 3, the heat dissipation device 20 may be one or more heat sinks disposed on the array body 10, and heat is passively transferred from the array body 10 to the heat sink. The heat dissipation device 20 can be in thermal contact with the vacuum chamber body to passively transfer heat from the array body 10. The heat dissipation device 20 may include a cooling channel for circulating a cooling fluid through the array body 10, and actively transfer heat from the array body 10 to the cooling fluid.

[0045] As shown in FIG. 4, an embodiment of the present disclosure provides a method 200 for selecting a subset of beams from a multi-beam array system. The method 200 can include the following steps.

[0046] In step 201, the array body is provided in proximity to the beam source. The array body may comprise a plurality of apertures, and at least two of the apertures may have different geometric shapes. For example, each of the plurality of apertures may have a different size or a different shape. Each of the plurality of apertures may be suitable for a specific operation of the multi-beam array system. For example, a circular aperture may be suitable for a hot spot inspection operation; a rectangular aperture is suitable for a swath operation; and a hexagonal aperture may be suitable for step and setting operations. Two of the plurality of apertures may have the same shape but different sizes. The smaller sized aperture may have a higher resolution than the larger aperture of the same shape. By arranging the array body such that one of the plurality of apertures intersects the optical axis of the beam source, unwanted beams from the beam source can be clipped by the array body and prevented from being directed towards the wafer. Thus, a subset of the beams from the beam source may be selected based on the geometric shape of the aperture that intersects the optical axis.

[0047] In step 202, the array body is moved with respect to the optical axis of the beam source such that one of the apertures intersects the optical axis. By moving the array body, different apertures of the plurality of apertures can be made to intersect the optical axis. Thus, different subsets of the beams may be selected based on the different geometric shapes of the different apertures that intersect the optical axis.

[0048] The plurality of apertures may be arranged one-dimensionally within the array body. For example, the plurality of apertures may be linearly arranged such that the center points of each of the apertures are collinear. In this way, the array body can be moved along a single axis perpendicular to the optical axis to change which aperture intersects the optical axis. A linear actuator can be provided that is configured to move the array body in the X direction perpendicular to the optical axis of the beam source. Accordingly, step 202 can include moving the array body in the X direction via the linear actuator such that one of the apertures intersects the optical axis.

[0049] The plurality of apertures may be circularly arranged such that the center points of each of the apertures are annular. In this way, the array body can be rotated around a single axis parallel to the optical axis to change which aperture intersects the optical axis. A rotational actuator may be provided, and the rotational actuator may be configured to rotate the array body circumferentially about a rotational axis perpendicular to the array body and parallel to the optical axis. Accordingly, step 202 can include rotating the array body circumferentially via the rotational actuator such that one of the apertures intersects the optical axis.

[0050] The plurality of apertures may be arranged two-dimensionally within the array body. For example, the plurality of apertures may be arranged in a grid such that the center point of each aperture corresponds to an X-Y position on the grid. In this way, the array body can move along two axes each perpendicular to the optical axis, and change which aperture intersects the optical axis according to the X-Y position of each aperture. A pair of linear actuators can be provided that are configured to move the array body in the X direction and the Y direction respectively with respect to the optical axis of the beam source, and each linear actuator is perpendicular to the optical axis and perpendicular to each other. Accordingly, step 202 can include moving the array body in the X direction and the Y direction via the pair of linear actuators such that one of the apertures intersects the optical axis.

[0051] In step 203, an electron beam is generated around the optical axis using a beam source.

[0052] In step 204, the electron beam is directed through the array body to select a subset of the electron beam based on the shape of an aperture that intersects the optical axis. Thus, only a portion of the electron beam can pass through the aperture.

[0053] At least one of the plurality of apertures may be circular. The circular aperture may be suitable for hot spot inspection operations. Thus, when the aperture intersecting the optical axis is circular, method 200 may further include performing a hot spot inspection operation on a portion of the wafer disposed within the optical axis downstream of the array body.

[0054] At least one of the plurality of apertures may be rectangular. The rectangular aperture is suitable for swath operations. Thus, when the aperture intersecting the optical axis is rectangular, method 200 may further include performing a swath operation on a portion of the wafer disposed within the optical axis downstream of the array body.

[0055] At least one of the plurality of apertures may be hexagonal. The hexagonal aperture may be suitable for step and setting operations. Thus, when the aperture intersecting the optical axis is hexagonal, method 200 may further include performing step and setting operations on a portion of the wafer located within the optical axis downstream of the array body.

[0056] In method 200, different subsets of the electron beam may be selected by the following additional steps.

[0057] The array body is moved relative to the optical axis of the beam source via an actuator such that different apertures of the apertures intersect the optical axis.

[0058] The electron beam is directed through the array body to select different subsets of the electron beam based on the different shapes of apertures that intersect the optical axis.

[0059] FIG. 5 is a block diagram of an embodiment of system 300. System 300 includes a wafer inspection tool (including electron column 301) configured to generate an image of wafer 304.

[0060] The wafer inspection tool includes an output acquisition subsystem including at least an energy source and a detector. The output acquisition subsystem may be an electron beam-based output acquisition subsystem. For example, in one embodiment, the energy directed at wafer 304 includes electrons and the energy detected from wafer 304 includes electrons. In this way, the energy source can be an electron beam source. In one such embodiment shown in FIG. 5, the output acquisition subsystem includes an electron column 301 coupled to computer subsystem 302. Stage 310 can hold wafer 304.

[0061] As also shown in FIG. 5, electron column 301 includes an electron beam source 303 configured to generate electrons that are focused onto wafer 304 by one or more elements 305. Electron beam source 303 may include, for example, a cathode source or an emitter tip. The one or more elements 305 can include, for example, a gun lens, an anode, a beam limiting aperture, a gate valve, a beam current selection aperture, an objective lens, and a scanning subsystem, all of which can include any such suitable elements known in the art. Aperture array 100 can be disposed upstream of one or more of the elements 305, proximate to electron beam source 303. In another embodiment, aperture array 100 may be disposed proximate to electron beam source 303 between two of the one or more elements 305. Although only one beam is shown in FIG. 5, multiple electron beam sources 303 may be provided, or the electron beam source may be configured to emit an array of multiple beams.

[0062] Electrons (e.g., secondary electrons) returning from the wafer 304 can be focused onto the detector 307 by one or more elements 306. The one or more elements 306 can include a scanning subsystem, which can be, for example, the same scanning subsystem as that included in the element 305.

[0063] The electron column 301 may also include any other suitable elements known in the art.

[0064] The electron column 301 is shown in FIG. 5 as being configured such that electrons are directed at the wafer 304 at an oblique angle of incidence and scattered from the wafer 304 at another oblique angle, but the electron beam may be directed at the wafer 304 and scattered therefrom at any suitable angle. Further, the electron beam-based output acquisition subsystem can be configured to use multiple modes to generate an image of the wafer 304 (e.g., having different illumination angles, collection angles, etc.). The multiple modes of the electron beam-based output acquisition subsystem can differ in any image generation parameter of the output acquisition subsystem.

[0065] The computer subsystem 302 may be coupled to the detector 307 as described above. The detector 307 can detect electrons returning from the surface of the wafer 304, thereby forming an electron beam image of the wafer 304. The electron beam image can include any suitable electron beam image. The computer subsystem 302 can be configured to generate an image of the wafer 304 or to perform any of the functions described herein using the output of the detector 307 and / or the electron beam image. The computer subsystem 302 may be configured to perform any additional steps described herein. The system 300 including the output acquisition subsystem shown in FIG. 5 can be further configured as described herein.

[0066] Note that FIG. 5 is provided herein to schematically illustrate the configuration of an electron beam-based output acquisition subsystem that may be used in the embodiments described herein. The electron beam-based output acquisition subsystem configuration described herein may be modified to optimize the performance of the output acquisition subsystem as is typically done when designing a commercial output acquisition system. Additionally, the systems described herein may be implemented using existing systems (e.g., by adding the functionality described herein to an existing system). For some such systems, the methods described herein may be provided as optional functionality of the system (e.g., in addition to other functionality of the system). Alternatively, the systems described herein may be designed as completely new systems.

[0067] The output acquisition subsystem is described above as an electron beam-based output acquisition subsystem, but the output acquisition subsystem may be an ion beam-based output acquisition subsystem. Such an output acquisition subsystem may be configured as shown in FIG. 5, except that the electron beam source may be replaced with any suitable ion beam source known in the art. Additionally, the output acquisition subsystem may be any other suitable ion beam-based output acquisition subsystem, such as those included in commercially available focused ion beam (FIB) systems, helium ion microscope (HIM) systems, and secondary ion mass spectrometry (SIMS) systems.

[0068] Computer subsystem 302 includes a processor 308 and an electronic data storage unit 309. Processor 308 may include a microprocessor, a microcontroller, or other device.

[0069] The computer subsystem 302 may be coupled to the components of the system 300 in any suitable manner (e.g., via one or more transmission media that may include wired and / or wireless transmission media) such that the processor 308 can receive the output. The processor 308 may be configured to perform several functions using the output. The wafer inspection tool can receive instructions or other information from the processor 308. The processor 308 and / or the electronic data storage unit 309 may optionally communicate electronically with another wafer inspection tool, wafer measurement tool, or wafer review tool (not shown) to receive additional information or send instructions.

[0070] The processor 308 communicates electronically with a wafer inspection tool such as an actuator for the detector 307 or the aperture array 100. The processor 308 may be configured to process an image generated using measurements from the detector 307 or select an aperture within the aperture array 100.

[0071] The computer subsystem 302, other systems, or other subsystems described herein may be part of various systems, including a personal computer, image computer, mainframe computer system, workstation, network appliance, Internet appliance, or other device. The subsystem or system may also include any suitable processor known in the art, such as a parallel processor. Additionally, the subsystem or system may include a platform with high-speed processing and software, either as a stand-alone tool or a network tool.

[0072] The processor 308 and the electronic data storage unit 309 can be arranged within the system 300 or another device or can alternatively be part thereof. In one example, the processor 308 and the electronic data storage unit 309 can be part of a stand-alone control unit or can be a centralized quality control unit. A plurality of processors 308 or electronic data storage units 309 may be used.

[0073] The processor 308 can actually be implemented by any combination of hardware, software, and firmware. Also, its functions as described herein may be executed by one unit or may be divided among different components, each of which may in turn be implemented by any combination of hardware, software, and firmware. The program code or instructions for the processor 308 to implement various methods and functions may be stored in a readable storage medium such as the memory within the electronic data storage unit 309 or other memory.

[0074] If the system 300 includes a plurality of computer subsystems 302, different subsystems can be coupled to each other so that images, data, information, instructions, etc. can be transmitted between the subsystems. For example, one subsystem can be coupled to an additional subsystem by any suitable transmission medium including any suitable wired and / or wireless transmission medium known in the art. Two or more of such subsystems may also be effectively coupled by a shared computer-readable storage medium (not shown).

[0075] The processor 308 may be configured to perform some functions using the output of the system 300 or other output. For example, the processor 308 may be configured to transmit the output to the electronic data storage unit 309 or another storage medium. The processor 308 may further be configured as described herein.

[0076] The processor 308 or computer subsystem 302 may be part of a defect review system, inspection system, measurement system, or some other type of system. Accordingly, the embodiments disclosed herein describe several configurations that can be adjusted in several ways for systems having different capabilities that are more or less suitable for different applications.

[0077] The processor 308 may be configured according to any of the embodiments described herein. The processor 308 may also be configured to perform other functions or additional steps using the output of the system 300 or using images or data from other sources.

[0078] The processor 308 may be communicatively coupled to any of the various components or subsystems of the system 300 in any manner known in the art. Further, the processor 308 may be configured to receive and / or obtain data or information from other systems (e.g., inspection results from an inspection system such as a review tool, a remote database including design data, etc.) via a transmission medium that may include wired and / or wireless portions. In this way, the transmission medium may serve as a data link between the processor 308 and other subsystems of the system 300 or systems external to the system 300.

[0079] The various steps, functions, and / or operations of the systems 300 and methods disclosed herein are performed by one or more of the following: electronic circuits, logic gates, multiplexers, programmable logic devices, ASICs, analog or digital controls / switches, microcontrollers, or computing systems. Program instructions implementing methods such as those described herein may be transmitted via a carrier medium or stored on a carrier medium. The carrier medium may include storage media such as read-only memory, random access memory, magnetic or optical disks, non-volatile memory, solid-state memory, magnetic tape, etc. The carrier medium may include transmission media such as wires, cables, or wireless transmission links. For example, the various steps described throughout this disclosure may be performed by a single processor 308 (or computer subsystem 302), or alternatively, by a plurality of processors 308 (or a plurality of computer subsystems 302). Further, different subsystems of the system 300 may include one or more computing or logic systems. Accordingly, the above description should not be construed as a limitation on the present disclosure, but rather as merely illustrative thereof.

[0080] Although described with respect to an electron beam, the aperture array 100 can also be used with an ion beam or other particle beam system.

[0081] Although the present disclosure has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present disclosure may be made without departing from the scope of the present disclosure. Accordingly, the present disclosure is considered to be limited only by the appended claims and their proper interpretation.

Claims

1. An aperture array arranged in a multi-beam array system having a multi-beam, An array body arranged close to a beam source, comprising a plurality of apertures, at least two of said apertures having different geometric shapes, each of said apertures having a dimension smaller than the beam dimension of said beam, and at least one of said plurality of apertures being hexagonal, array body Comprising, The array body is movable relative to the optical axis of the beam source via an actuator, whereby a subset of the beams from the beam source is selected based on the shape of the aperture intersecting the optical axis, and when the aperture intersecting the optical axis is hexagonal, a wafer located within the optical axis downstream of the array body is caused to perform a step and settle operation by a controller of the multi-beam array system. Aperture array.

2. The aperture array according to claim 1, wherein at least one of said plurality of apertures is circular.

3. The aperture array according to claim 1, wherein at least one of said plurality of apertures is rectangular.

4. The aperture array according to claim 1, wherein two of said plurality of apertures have different sizes and the same shape.

5. The aperture array according to claim 1, wherein said plurality of apertures are arranged one-dimensionally within said array body.

6. The aperture array according to claim 5, wherein the actuator comprises a linear actuator for moving the array body in the X direction with respect to the optical axis of the beam source, and the X direction is perpendicular to the optical axis.

7. The aperture array according to claim 5, wherein the actuator comprises a rotary actuator configured to rotate the array body about a rotation axis with respect to the optical axis of the beam source, and the rotation axis is parallel to the optical axis.

8. The aperture array according to claim 1, wherein said plurality of apertures are arranged two-dimensionally within said array body.

9. The actuator includes a pair of linear actuators configured to move the array body in the X direction and the Y direction with respect to the optical axis of the beam source, and the X direction and the Y direction are perpendicular to the optical axis and perpendicular to each other. The aperture array according to claim 8, characterized in that.

10. The aperture array according to claim 1, wherein the array body is made of aluminum nitride, polycrystalline diamond, graphite, molybdenum, or tungsten.

11. The aperture array according to claim 1, further comprising a heat dissipation device disposed on the array body and configured to actively or passively dissipate heat from the array body.

12. The aperture array according to claim 1, wherein the distance between the array body and the beam source is 10 cm to 20 cm.

13. The aperture array according to claim 1, wherein the beam source is an electron beam source.

14. A method of selecting a subset of beams from a multi-beam array system comprising multi-electron beams, Providing an array body in proximity to a beam source, the array body comprising a plurality of apertures, at least two of the apertures having different geometries, each of the apertures having a dimension smaller than the beam dimension of the electron beam, and at least one of the plurality of apertures being hexagonal; step, Moving the array body relative to the optical axis of the beam source via an actuator such that one of the apertures intersects the optical axis; Generating the electron beam around the optical axis using the beam source; Passing at least one of the electron beams through the array body to select a subset of the electron beams based on the shape of the aperture intersecting the optical axis, and when the aperture intersecting the optical axis is hexagonal, the controller of the multi-beam array system causes the wafer located within the optical axis downstream of the array body to perform a step and settle operation. step, A method comprising.

15. At least one of the plurality of apertures is circular, and when the aperture intersecting the optical axis is circular, further, the hot spot inspection operation includes a step of performing a hot spot inspection operation on a portion of the wafer disposed within the optical axis downstream of the array body. The method according to claim 14, characterized in that it comprises.

16. At least one of the plurality of apertures is rectangular, and when the aperture intersecting the optical axis is rectangular, further, a step of performing a swath operation on a portion of the wafer disposed within the optical axis downstream of the array body. The method according to claim 14, characterized in that it comprises.

17. Moving the array body relative to the optical axis of the beam source via the actuator such that different apertures of the apertures intersect the optical axis; Directing the electron beam through the array body to select different subsets of the electron beam based on the shape of different apertures of the apertures intersecting the optical axis; The method according to claim 14, further comprising.

18. The distance between the array body and the beam source is 10 cm to 20 cm. The method according to claim 14, characterized in that.

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