Wafer workpiece table and electron beam detection equipment

Abstract

The invention discloses a wafer workpiece table and electron beam detection equipment. The wafer workpiece table comprises a base, a driving assembly and a bearing part, the base is provided with a plurality of bearing columns, and the bearing columns are used for transferring wafers; the driving assembly is installed on the base and used for providing driving force. The bearing part is installed on the driving assembly, the bearing part comprises an installation plate and a suction cup, the first side of the installation plate is installed on the driving assembly, an isolation layer is arranged on the second side of the installation plate and used for isolating a high-voltage electric field, and the suction cup is installed on the installation plate. And the sliding assembly is used for sliding along the bearing column under the driving of the driving assembly so as to pick and place the wafer. The bearing column of the wafer workpiece table is fixed, the suction cup is driven by the driving assembly to slide along the bearing column, and the electronic gun does not need to be adjusted; the isolating layer of the mounting plate can enable the wafer workpiece table to be suitable for high-energy electron beam equipment, and the wafer workpiece table has the characteristics of low failure rate, high efficiency and strong universality.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor technology, and in particular relates to a wafer workpiece stage and electron beam detection equipment. Background Art

[0002] Electron beam testing equipment is a key device for testing chip performance and defects in the semiconductor manufacturing process. Among them, the wafer worktable, as the core component of the electron beam testing equipment, must not only ensure fast and stable wafer placement, but also maintain a nanometer-level precise working distance with the electron gun of the electron beam testing equipment.

[0003] In the related art, the wafer worktable includes an electrostatic chuck and a supporting column. The electrostatic chuck remains stationary, and the supporting column is externally connected to an actuator. The supporting column slides relative to the electrostatic chuck, thereby exchanging the wafer with an external transmission mechanism. It has low working efficiency and poor versatility. Summary of the invention

[0004] The embodiments of the present application provide a wafer worktable and an electron beam detection device, which can avoid jamming and drifting during wafer transmission and improve efficiency and versatility.

[0005] In the first aspect, an embodiment of the present application provides a wafer worktable, which includes a base, a drive assembly and a carrier; the base is provided with a plurality of carrier columns, and the carrier columns are used for transferring wafers; the drive assembly is mounted on the base for providing driving force; the carrier is mounted on the drive assembly, and the carrier includes a mounting plate and a suction cup, the mounting plate is mounted on the drive assembly on a first side, an isolation layer is provided on a second side of the mounting plate, and the isolation layer is used to isolate high-voltage electric fields; the suction cup is mounted on the mounting plate, and is used to slide along the carrier columns under the drive of the drive assembly to pick up and place wafers.

[0006] Furthermore, the carrier also includes an isolation plate, which is installed on the mounting plate, and an avoidance hole is provided on the isolation plate. The suction cup is located in the avoidance hole, and the outer peripheral surface of the suction cup is connected to the side wall of the avoidance hole; a grounding hole is provided on the isolation plate, and a grounding wire is provided on the grounding hole.

[0007] Furthermore, on the side away from the mounting plate, the isolation plate is provided with an isolation ring along the periphery of the avoidance hole; on the side away from the mounting plate, the distance between the surface of the isolation ring and the mounting plate is greater than the distance between the surface of the suction cup and the mounting plate, so that the isolation ring can be used to limit the wafer on the suction cup.

[0008] Further, the driving component includes a macro-motion component, and the macro-motion component includes a first slider, a driving member and a second slider; taking the direction intersecting the axis of the supporting column as the first direction, and taking the direction parallel to the axis of the supporting column as the second direction, the first slider slides with the base along the first direction, and a first inclined surface is provided on the top of the first slider, and the angle between the first inclined surface and the first direction is less than 45°; the driving member is installed on the base and connected to the first slider, and is used to drive the first slider to slide along the first direction; the second slider slides with the base along the second direction, the second slider is connected to the supporting member, and a second inclined surface is provided at the bottom of the second slider, and the second inclined surface slides with the first inclined surface to drive the suction cup to translate along the second direction.

[0009] Furthermore, the driving component includes a servo motor, which is mounted on the base and located in the cavity of the first slider. The servo motor is connected to a host computer. A magnetic shielding layer is provided on the wall of the cavity, and the thickness of the magnetic shielding layer is 0.1 mm to 0.5 mm.

[0010] Furthermore, the driving member also includes a ball screw pair, which is installed on the base and connected to the servo motor and the first slider. The ball screw pair is used to drive the first slider to slide under the drive of the servo motor.

[0011] Further, the base is provided with a first guide rail along the first direction, and the first guide rail is slidably matched with the first slider; the base is provided with a second guide rail along the second direction, and the second guide rail is slidably matched with the second slider; along the first direction, the second guide rail is located on one side of the first guide rail.

[0012] Furthermore, it also includes a detection component, which includes: a laser ruler, a shading sheet and a photoelectric sensor; the laser ruler is installed on the base to detect the displacement of the second slider; the shading sheet is installed on the first slider; the photoelectric sensor is installed on the base to cooperate with the shading sheet to detect the displacement of the first slider; the laser ruler and the photoelectric sensor are both externally connected to a host computer.

[0013] Furthermore, the drive assembly also includes a micro-motion assembly, which includes a piezoelectric ceramic, a connecting plate and a flexible member; the piezoelectric ceramic is installed on the second slider and connected to the host computer for extension and contraction in the second direction; the connecting plate includes a first connecting part, a second connecting part and a third connecting part, one end of the second connecting part is connected to the first connecting part, and the other end is connected to the third connecting part, the second connecting part is provided with a weak section at the connection between the first connecting part and the third connecting part, and the weak section is used to guide deformation between the first connecting part and the second connecting part and between the second connecting part and the third connecting part, the first connecting part is connected to the second slider, the second connecting part is connected to the piezoelectric ceramic, and the third connecting part is connected to the supporting member; one end of the flexible member is connected to the second slider, and the other end is connected to the third connecting part, and is used to pull the third connecting part in a direction away from the supporting member.

[0014] Furthermore, a protective shell is provided on the outer side of the piezoelectric ceramic, and the protective shell is used to provide electric field shielding for the piezoelectric ceramic.

[0015] In a second aspect, an embodiment of the present application further provides an electron beam detection device, which includes the wafer workpiece table described in any of the above technical solutions.

[0016] The embodiment of the present application provides a wafer worktable and electron beam detection equipment, in which a supporting column of the wafer worktable is installed on a base, and the supporting column is fixed, so as to avoid jamming and wafer drift caused by rapid movement of the wafer driven by the supporting column, thereby reducing the failure rate; the suction cup slides along the supporting column driven by the driving component, which can not only realize the wafer taking and placing, but also adjust the distance between the suction cup and the electron gun when detecting wafers of different thicknesses, without adjusting the parameters of the electron gun; the isolation layer of the mounting plate can isolate the divergence of the high-voltage electric field and reduce the interference of the high-voltage electric field on electronic components, so that the wafer worktable can be applied to high-energy electron beam equipment, thereby reducing the failure rate of the wafer worktable, improving efficiency and versatility, and facilitating large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 A schematic structural diagram of a wafer worktable from one perspective in some embodiments of the present application;

[0019] Figure 2 A schematic structural diagram of a wafer worktable from another perspective of some embodiments of the present application;

[0020] Figure 3 A schematic structural diagram of a support member from one perspective of some embodiments of the present application;

[0021] Figure 4 This is a schematic diagram of installing the first sliding block on the base in some embodiments of the present application;

[0022] Figure 5 This is a schematic diagram of the connection between the second sliding block and the driving member in some embodiments of the present application;

[0023] Figure 6 A schematic structural diagram of a driving member from one perspective of some embodiments of the present application;

[0024] Figure 7 This is a test diagram of the repeatability of the wafer workpiece stage in the related technology;

[0025] Figure 8 This is a test diagram of the repeatability positioning accuracy of the wafer worktable in some embodiments of the present application.

[0026] In the figure: 1-base; 11-bearing column; 12-first guide rail; 13-second guide rail; 2-driving assembly; 21-first slider; 211-first inclined plane; 212-third guide rail; 22-driving member; 23-second slider; 231-second cut-off surface; 24-piezoelectric ceramic; 25-protective shell; 26-connecting plate; 261-first connecting part; 262-second connecting part; 263-third connecting part; 264-weak section; 27-flexible member; 3-bearing member; 31-mounting plate; 32-suction cup; 321-through hole; 33-isolation plate; 331-isolation ring; 332-grounding hole; 4-detection assembly; 41-laser ruler; 42-shading sheet; 43-photoelectric sensor. DETAILED DESCRIPTION

[0027] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0029] Electron beam inspection equipment is a key device for detecting chip performance and defects in the semiconductor manufacturing process. The wafer worktable, as its most core component, must not only ensure fast and smooth wafer placement, but also provide nanometer-level precise working distance for the electron gun. Therefore, extremely high requirements are placed on the wafer worktable.

[0030] During the wafer transfer process, the wafer worktable needs to frequently interact with other transfer mechanisms to pick up and place wafers. In the related art, the wafer worktable drives the ejector in the vacuum chamber through a motor arranged outside the vacuum chamber, and the ejector drives the supporting column to rise and fall through connecting parts such as connecting rods, thereby completing the wafer placement on the electrostatic chuck.

[0031] The inventors found that the wafer worktable transmission mechanism of the related technology is complicated. When the wafer transmission speed is accelerated, the supporting column will gradually get stuck and fail to work, accompanied by the overall drift of the wafer, which is not conducive to the improvement of equipment output. In addition, the electron gun has high requirements for the accuracy of the working distance. It is difficult to ensure the working distance by relying on the design and assembly accuracy. The debugging time is long and the efficiency is low. Different models of electron guns have different working distances, and different wafers have different thicknesses. They need to match wafer worktables of different heights. The wafer worktables of the related technology have poor versatility and are not conducive to large-scale production.

[0032] In addition, the inventors found that the voltage applied to the wafer by ordinary electron beam detection equipment is low, and the electric field formed has no obvious effect on the electronic components near the wafer worktable. In order to control the energy of the electron beam during the detection process, the high-energy electron beam equipment will load the surface of the wafer with a high voltage of tens of thousands of volts, which is likely to cause great interference to the electronic components.

[0033] In view of this, an embodiment of the present application provides a wafer workpiece stage and electron beam detection equipment.

[0034] Please refer to Figures 1 to 3 , Figure 1 A schematic structural diagram of a wafer worktable from one perspective in some embodiments of the present application; Figure 2 A schematic structural diagram of a wafer worktable from another perspective of some embodiments of the present application; Figure 3 This is a schematic structural diagram of a carrier from one perspective of some embodiments of the present application.

[0035] In the first aspect, an embodiment of the present application provides a wafer worktable, which includes a base 1, a drive assembly 2 and a carrier 3; the base 1 is provided with a plurality of carrier columns 11; the drive assembly 2 is mounted on the base 1; the carrier 3 is mounted on the drive assembly 2, the carrier 3 includes a mounting plate 31 and a suction cup 32, the first side of the mounting plate 31 is mounted on the drive assembly 2, the second side of the mounting plate 31 is provided with an isolation layer, and the suction cup 32 is mounted on the mounting plate 31.

[0036] In the wafer worktable, the base 1 is used to provide an installation foundation for other components to be installed on the base 1. A plurality of bearing columns 11 are provided on the base 1, and the bearing columns 11 are installed on the base 1 for transferring wafers. When placing and taking wafers, an external transmission mechanism can place the wafer on the bearing columns 11 or take the wafer from the bearing columns 11, and the driving assembly 2 can provide driving force for the bearing member 3, driving the bearing member 3 to slide in a direction parallel to the axis of the bearing column 11.

[0037] The mounting plate 31 of the bearing member 3 is mounted on the driving assembly 2, and the suction cup 32 is mounted on the mounting plate 31. An isolation layer is provided on the second side of the mounting plate 31, and the isolation layer is used to isolate the high voltage electric field. The isolation layer can be formed on the second side of the mounting plate 31 and become one with the mounting plate 31. For example, the isolation layer can be coated on the second side of the mounting plate 31 to form a shielding body; the isolation layer can also be a plate installed on the second side of the mounting plate 31, which is separated from the mounting plate 31 and is only located on the second side of the mounting plate 31 in terms of spatial position relationship, and the plate forms a shielding body.

[0038] Exemplarily, the isolation layer may be a glass fiber reinforced plastic material, a ceramic material, etc., which is coated on the second side of the mounting plate 31 ; the isolation layer may also be a ceramic plate, which is mounted on the second side of the mounting plate 31 .

[0039] The suction cup 32 is used to slide along the bearing column 11 under the drive of the driving assembly 2 to pick up and place the wafer. A plurality of insertion holes 321 may be provided on the suction cup 32, and the bearing column 11 is located in the insertion holes 321 and corresponds to the insertion holes 321 one by one. The insertion holes 321 are located outside the bearing column 11, and the insertion holes 321 are arranged on the suction cup 32. When the suction cup 32 picks up and places the wafer, the wafer can be picked up and placed from the outside of each bearing column 11, so that the wafer is evenly stressed and not easily damaged.

[0040] When the suction cup 32 slides, it moves downward when it is close to the base 1, and moves upward when it is away from the base 1. When the suction cup 32 slides upward and its upper end surface passes over the top of the supporting column 11, the wafer is lifted up and separated from the supporting column 11 for detection by the electron beam detection equipment; when the suction cup 32 slides downward and the top of the supporting column 11 is exposed on the upper end surface of the suction cup 32, the wafer is lifted up by the supporting column 11 and separated from the suction cup 32, and the wafer remains on the supporting column 11 for removal by the external transmission mechanism.

[0041] The bearing column 11 is fixedly mounted on the base 1, for example, it can be fastened to the base 1 by bolt connection, can be connected to the base 1 by welding, and can be connected to the base 1 by clamping. There are multiple bearing columns 11, for example, the number of bearing columns 11 can be three, four, five, or six.

[0042] As a power mechanism, the driving assembly 2 can provide driving force for linear motion. For example, the driving assembly 2 can be a gear rack mechanism driven by a power element, the power element can be a servo motor, the power element drives the gear to rotate, the gear drives the rack to slide through meshing, and the rack drives the bearing 3 to slide; the driving assembly 2 can be an electric cylinder to drive the bearing 3 to slide; the driving assembly 2 can also be a linear motor to drive the bearing 3 to slide.

[0043] The suction cup 32 serves as a carrier of the wafer and can provide a placement space for the wafer when the electron beam detection equipment detects the wafer. Exemplarily, the suction cup 32 can be connected to the wafer in the form of electrostatic adsorption.

[0044] In the technical scheme of the above embodiment, the supporting column 11 of the wafer worktable is installed on the base 1. When the wafer is handed over, the supporting column 11 is fixed, which can avoid jamming and wafer drift caused by the rapid movement of the wafer driven by the supporting column 11, thereby reducing the failure rate; the supporting member 3 slides along the supporting column 11 driven by the driving component 2, which can not only realize the wafer taking and placing, but also adjust the distance between the wafer and the electron gun when detecting wafers of different thicknesses, without the need to adjust the parameters of the electron gun; the isolation layer of the mounting plate 31 can isolate the divergence of the high-voltage electric field and reduce the interference of the high-voltage electric field on electronic components, so that the wafer worktable can be suitable for high-energy electron beam equipment, thereby reducing the failure rate of the wafer worktable, improving efficiency and versatility, and facilitating large-scale production.

[0045] In some embodiments, Figure 3 As shown, the bearing member 3 further includes an isolation plate 33, which is mounted on the mounting plate 31. The isolation plate 33 is provided with an avoidance hole, and the suction cup 32 is located in the avoidance hole. The outer peripheral surface of the suction cup 32 is connected to the side wall of the avoidance hole. The isolation plate 33 is provided with a grounding hole 332, which is used to connect the wire to the ground.

[0046] The isolation plate 33 and the suction cup 32 are of split design, that is, the isolation plate 33 and the suction cup 32 are two parts, which are formed separately and assembled on the same side of the mounting plate 31. For example, the suction cup 32 can be embedded in the avoidance hole, and the outer peripheral surface of the suction cup 32 is tightly fitted with the side wall of the avoidance hole.

[0047] When the isolation plate 33 and the suction cup 32 are located on the same side of the mounting plate 31 , both are installed on the isolation layer. The isolation plate 33 is in contact with the outer peripheral surface of the suction cup 32 and is located outside the suction cup 32 .

[0048] In the technical solution of the above embodiment, the suction cup 32 is located in the avoidance hole of the isolation plate 33, and the isolation plate 33 surrounds the outside of the suction cup 32, so that the high-voltage electric field can be carried on the outside of the suction cup 32, and the wire is connected to the ground through the grounding hole 332 to suppress the divergence of the high-voltage electric field and protect the electronic components. On the basis of setting an isolation layer on the mounting plate 31, setting an isolation plate 33 on the outside of the suction cup 32 can form a double-layer protection, which has a better inhibitory effect on the divergence of the high-voltage electric field.

[0049] In some embodiments, Figure 3 As shown, on the side away from the mounting plate 31, an isolation ring 331 is provided on the isolation plate 33 along the periphery of the avoidance hole; on the side away from the mounting plate 31, the distance between the surface of the isolation ring 331 and the mounting plate 31 is greater than the distance between the surface of the suction cup 32 and the mounting plate 31, so that the isolation ring 331 can be used to limit the wafer on the suction cup 32.

[0050] An isolation ring 331 is provided on the isolation plate 33, and the isolation ring 331 surrounds the outer side of the suction cup 32 and is higher than the top surface of the suction cup 32. Exemplarily, the isolation plate 33 and the suction cup 32 may be located on the same plane, and the isolation ring 331 protrudes from the surface of the plane.

[0051] In the technical solution of the above embodiment, an isolation ring 331 is provided on the isolation plate 33, and the isolation ring 331 can be surrounded by the outer side of the suction cup 32. When the suction cup 32 carries a wafer, the isolation ring 331 can be surrounded by the outer side of the wafer to play a protective role, limit the wafer, and prevent the wafer from drifting when taking and placing the wafer.

[0052] Please refer to Figures 4 to 6 , Figure 4 This is a schematic diagram of installing the first sliding block on the base in some embodiments of the present application; Figure 5 A schematic diagram of the connection between the second sliding block and the driving member in some embodiments of the present application; Figure 6 This is a schematic structural diagram of a driving member from one perspective of some embodiments of the present application.

[0053] In some embodiments, Figure 4 and Figure 5As shown, the driving assembly 2 includes a macro-motion assembly, and the macro-motion assembly includes a first slider 21, a driving member 22, and a second slider 23; the direction intersecting the axis of the bearing column 11 is the first direction, and the direction parallel to the axis of the bearing column 11 is the second direction. The first slider 21 slides with the base 1 along the first direction, and a first inclined surface 211 is provided on the top of the first slider 21. The angle between the first inclined surface 211 and the first direction is less than 45°. The driving member 22 is installed on the base 1 and connected to the first slider 21. The driving member 22 is used to drive the first slider 21 to slide along the first direction. The second slider 23 slides with the base 1 along the second direction. The second slider 23 is also connected to the bearing member 3. A second inclined surface is provided at the bottom of the second slider 23. The second inclined surface slides with the first inclined surface 211 to drive the suction cup 32 to translate along the second direction.

[0054] In the wafer worktable, the macro-motion component can regulate the displacement at a macro level (for example, at the millimeter level). The first direction intersects with the second direction, and preferably the first direction is perpendicular to the second direction. The first direction can be on a horizontal plane, and the second direction can be on a vertical plane. When the suction cup 32 rises and the wafer is obtained from the supporting column 11, the driving member 22 drives the first slider 21 to slide along the first direction, and then the first slider 21 squeezes the second slider 23, and the second slider 23 slides along the second direction under the joint action of the base 1 and the first slider 21, which can drive the suction cup 32 installed on the second slider 23 to rise and obtain the wafer from the supporting column 11. When the suction cup 32 descends and the wafer is placed on the supporting column 11, the driving member 22 drives the first slider 21 to slide in the opposite direction, and then the second slider 23 descends, driving the suction cup 32 to descend, and placing the wafer on the supporting column 11.

[0055] For example, when the first slider 21 and the base 1 are slidably matched, the first slider 21 and the second slider 23 are slidably matched, and the second slider 23 and the base 1 are slidably matched, a guide rail can be provided to provide a sliding guide, or a roller can be used to reduce friction.

[0056] The angle between the first inclined surface 211 and the first direction is less than 45°. Exemplarily, the inclination angle can be 20°, 22°, 24°, 26°, 28°, 30°, 32°, 34°, 36°, 38°, 40°, 42°, 44°, or any intermediate value between any two adjacent values ​​mentioned above.

[0057] When the angle between the first inclined surface 211 and the first direction is less than 45°, the horizontal displacement rate of the first slider 21 is greater than the vertical displacement rate of the second slider 23, and the first slider 21 and the second slider 23 realize speed reduction transmission. In the same period of time, the horizontal displacement of the first slider 21 is greater than the vertical displacement of the second slider 23. The driving member 22 is connected to the outside world when outputting thrust or pulling force outward, and there is an assembly error during the connection. The larger the displacement, the smaller the impact of the assembly error on the accuracy. For example, if the assembly error is 0.1mm, when the driving member 22 pushes outward by 5mm, the accuracy of its translation is 0.98, and when the driving member 22 pushes outward by 10mm, the accuracy of its translation is 0.99. The accuracy is improved as the translation distance increases.

[0058] The angle between the first inclined surface 211 and the first direction is less than 45°. Compared with using the driving member 22 to directly push the second slider 23, when the driving member 22 indirectly pushes the second slider 23 through the first slider 21, when the second slider 23 translates the same distance, the driving member 22 pushes or pulls the second slider 23 for a longer distance, and its accuracy is improved.

[0059] In the technical solution of the above embodiment, the first slider 21 slides synchronously with the second slider 23. The angle between the first inclined surface 211 and the first direction is less than 45°, which can reduce the error of the suction cup 32 when it is lifted and lowered, especially after the suction cup 32 reciprocates for many times, and the effect is particularly obvious, which can improve the repeated positioning accuracy of the wafer.

[0060] In some embodiments, Figure 4 and Figure 5 As shown, the base 1 is provided with a first guide rail 12 along the first direction, and the first guide rail 12 is slidably matched with the first slider 21. The base 1 is provided with a second guide rail 13 along the second direction, and the second guide rail 13 is slidably matched with the second slider 23. Along the first direction, the second guide rail 13 is located on one side of the first guide rail 12.

[0061] The first guide rail 12 is mounted on the base 1. The number of the first guide rails 12 can be multiple, for example, the number of the first guide rails 12 is two, and the two first guide rails 12 are arranged in parallel and are respectively located on both sides of the driving member 22. When providing a sliding guide for the first slider 21, the force of the first slider 21 can be balanced, and the motion accuracy of the first slider 21 can be improved. The second guide rail 13 is mounted on the base 1. The number of the second guide rails 13 can be multiple, for example, the number of the second guide rails 13 is two, and the two second guide rails 13 are arranged in parallel, and the force of the second slider 23 can be balanced, and the motion accuracy of the second slider 23 can be improved.

[0062] The base 1 includes a bottom plate arranged in a first direction and a vertical plate arranged in a second direction, the bottom plate and the vertical plate are arranged perpendicularly, the first guide rail 12 is mounted on the bottom plate, and the second guide rail 13 is mounted on the vertical plate. In terms of positional relationship, the second guide rail 13 is located on one side of the first guide rail 12. When the second slider 23 slides, the second guide rail 13 bears the pressure from the second slider 23 and the pressure from the vertical plate in the entire length direction, and the two pressures are in opposite directions.

[0063] A third guide rail 212 may also be provided on the first slider 21. The third guide rail 212 is installed on the first inclined surface 211 and tilts toward the base 1 along with the first inclined surface 211. There may be two third guide rails 212, and the two third guide rails 212 are arranged in parallel. The first slider 21 may be slidably matched with the second slider 23 through the third guide rail 212, thereby providing a sliding guide for the second slider 23.

[0064] In the technical solution of the above embodiment, the sliding cooperation between the first slider 21 and the base 1 is realized by setting the first guide rail 12, and the sliding cooperation between the second slider 23 and the base 1 is realized by setting the second guide rail 13, so that the motion accuracy of the first slider 21 and the second slider 23 can be improved and the sliding resistance can be reduced. In addition, the second guide rail 13 is located on one side of the first guide rail 12 along the first direction, and the second guide rail 13 is subjected to balanced force and has high guiding accuracy. In particular, when the second slider 23 is displaced in the second direction, the second guide rail 13 will not produce deflection due to its own creeping, so that the repeat positioning accuracy of the carrier 3 can be improved, and a stable environment can be provided for high-quality images of the detection process.

[0065] In some embodiments, Figure 4 and Figure 5 As shown, the driving member 22 includes a servo motor, which is mounted on the base 1 and located in the cavity of the first slider 21. The servo motor is connected to the host computer. A magnetic shielding layer is provided on the wall of the cavity, and the thickness of the magnetic shielding layer ranges from 0.1 mm to 0.5 mm.

[0066] A cavity is provided in the first slider 21, and the servo motor is located in the cavity, and then the first slider 21 can be enclosed outside the servo motor to provide protection for the servo motor. The servo motor can be a vacuum servo motor, which is connected to the host computer. Exemplarily, the thickness of the magnetic shielding layer can be any value among 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, and 0.5mm, or any intermediate value between any two adjacent values ​​mentioned above. The magnetic shielding layer is coated on the wall of the cavity with a magnetic shielding material (electroplating, painting, etc. can be adopted), and the magnetic shielding material is a magnetic shielding material that is non-magnetic in itself, such as Permalloy.

[0067] When the driving member 22 uses a servo motor as a power source, the servo motor can be used in combination with a transmission mechanism, so as to convert the rotary motion of the servo motor into a translational motion, thereby forming a thrust or a pull on the first slider 21. For example, the transmission mechanism can be a gear and a rack, the rack is mounted on the first slider 21, the gear is mounted on the servo motor, and the servo motor pushes and pulls the first slider 21 through the meshing of the gear and the rack; the transmission mechanism can also be a ball screw pair, and the first slider 21 is pushed and pulled through the ball screw pair.

[0068] In the technical solution of the above embodiment, the first slider 21 is wrapped around the outside of the servo motor, which can shield the servo motor from the high-voltage electric field formed during wafer detection and prevent the servo motor from being damaged. A magnetic shielding layer is provided on the wall surface of the cavity of the first slider 21, which can also shield the magnetic field formed when the servo motor is running, avoid interference with wafer detection, and improve detection accuracy.

[0069] In some embodiments, Figure 4 and Figure 5 As shown, the driving member 22 includes a servo motor and a ball screw pair. The ball screw pair is installed on the base 1 and connected to the servo motor and the first slider 21. The ball screw pair can drive the first slider 21 to slide under the drive of the servo motor.

[0070] In the technical solution of the above embodiment, the driving is realized by the servo motor and the ball screw pair, which can improve the driving accuracy and stability. The servo motor is externally connected to the host computer, and a closed-loop control can be formed under the control of the host computer.

[0071] In some embodiments, Figure 5 and Figure 6 As shown, the drive assembly 2 also includes a micro-motion assembly, which includes a piezoelectric ceramic 24, a connecting plate 26 and a flexible member 27. The piezoelectric ceramic 24 is mounted on the second slider 23 and is connected to the host computer. The connecting plate 26 includes a first connecting portion 261, a second connecting portion 262 and a third connecting portion 263, one end of the second connecting portion 262 is connected to the first connecting portion 261, and the other end is connected to the third connecting portion 263, and the second connecting portion 262 is provided with a weak section 264 at the connection between the first connecting portion 261 and the third connecting portion 263. The first connecting portion 261 is connected to the second slider 23, the second connecting portion 262 is connected to the piezoelectric ceramic 24, and the third connecting portion 263 is connected to the bearing member 3. One end of the flexible member 27 is connected to the second slider 23, and the other end is connected to the third connecting portion 263.

[0072] The micro-motion assembly is used to adjust the displacement at the microscopic level (e.g., nanometer level) and adjust the position of the suction cup 32. The piezoelectric ceramic 24 expands and contracts in the second direction, and when it expands, it can drive the connecting plate 26 to deform, thereby causing the bearing member 3 (mounting plate 31) connected to the connecting plate 26 to displace.

[0073] The first connection portion 261 is connected to the second slider 23. When connected, the first connection portion 261 and the second slider 23 can be fixedly connected by bolt fastening, welding connection, clamping connection, etc. The second connection portion 262 is connected to the piezoelectric ceramic 24. When connected, the second connection portion 262 and the piezoelectric ceramic 24 can be fixedly connected by bolt fastening. The third connection portion 263 is connected to the carrier 3. When connected, the third connection portion 263 and the carrier 3 can be fixedly connected by bolt fastening, welding connection, clamping connection, etc.

[0074] The first connection part 261 is fixedly connected to the second slider 23, and the third connection part 263 is connected to the second slider 23 through the flexible member 27. The second connection part 262 is provided with a weak section 264 at the connection between the first connection part 261 and the third connection part 263. The thickness of the connection plate 26 is thinned in the weak section 264, and the yield strength is reduced. When the piezoelectric ceramic 24 drives the second connection part 262 to move, the weak section 264 guides the deformation between the first connection part 261 and the second connection part 262 and between the second connection part 262 and the third connection part 263. Exemplarily, the connection plate 26 can be made of beryllium copper.

[0075] The flexible member 27 is connected between the third connection portion 263 and the second slider 23, and is used to pull the third connection portion 263 in a direction away from the carrier 3. For example, the flexible member 27 can be a tension spring, a rubber column, or the like.

[0076] When the piezoelectric ceramic 24 drives the second connection part 262 to displace, the first connection part 261 plays a restraining role at one end of the second connection part 262, and the third connection part 263 also plays a restraining role at the other end of the second connection part 262. Exemplarily, when the second connection part 262 rises by 10 μm, the first connection part 261 does not displace, and after the plastic deformation of the two weak sections 264, the displacement amplitude of the third connection part 263 is greatly reduced to less than 10 μm.

[0077] In the technical solution of the above embodiment, the driving component 2 drives the carrier 3 to move through the piezoelectric ceramic 24, and can achieve micro-adjustment of the carrier 3 under the control of the external host computer. When connected with the carrier 3, the connecting plate 26 is provided with a first connecting portion 261, a second connecting portion 262, and a third connecting portion 263, as well as a weak section 264, and adopts the form of applying force by the flexible member 27 and connecting with the second slider 23, which can further reduce the adjustment amplitude during micro-adjustment, thereby further improving the adjustment accuracy.

[0078] In some embodiments, Figure 5 and Figure 6As shown, a protective shell 25 is disposed on the outer side of the piezoelectric ceramic 24 , and the protective shell 25 can provide electric field shielding for the piezoelectric ceramic 24 .

[0079] The piezoelectric ceramic 24 is mounted on the second slider 23 and fixedly connected to the second slider 23, and its axis is parallel to the second direction. The protective shell 25 surrounds the outer side of the piezoelectric ceramic 24 and wraps the piezoelectric ceramic 24 therein. The protective shell 25 is fixedly connected to the second slider 23, and the first connecting portion 261 can be indirectly connected to the second slider 23 by connecting the protective shell 25. The material of the protective shell 25 can be the same as or different from that of the isolation layer.

[0080] In the technical solution of the above embodiment, the protective shell 25 is arranged on the outside of the piezoelectric ceramic 24, which can protect the piezoelectric ceramic 24 and shield the interference of the high-voltage electric field on the piezoelectric ceramic 24, so that the wafer worktable can be suitable for high-energy electron beam equipment.

[0081] In some embodiments, Figure 4 and Figure 5 As shown, the first slider 21 is provided with a first cut-off surface, and the second slider 23 is provided with a second cut-off surface 231 . The first cut-off surface can abut against the second cut-off surface 231 , so as to limit the second slider 23 .

[0082] The first cut-off surface and the second cut-off surface 231 fit together when they are in contact, and their contours overlap. The first cut-off surface is located at the end of the first inclined surface 211 away from the base 1, and the second cut-off surface 231 is located at the end of the second inclined surface away from the base 1. When the first cut-off surface and the second cut-off surface 231 are in contact, it can be used as a basis for judging whether the second slider 23 moves to the limit position, thereby providing a limit for the second slider 23. Exemplarily, the first cut-off surface and the second cut-off surface 231 can both be planes, and the plane gradually tilts toward the base 1 when extending in the opposite direction to the first direction; the first cut-off surface and the second cut-off surface 231 can both be arc surfaces, and on the arc surface, the line between the two end points is located between any other point on the arc surface and the base 1.

[0083] In the technical solution of the above embodiment, a first cut-off surface is set on the first slider 21, and a second cut-off surface 231 is set on the second slider 23. The first cut-off surface and the second cut-off surface 231 can be abutted against each other to limit the second slider 23, which helps to improve the reliability of the displacement of the second slider 23.

[0084] In some embodiments, Figure 4 As shown, the wafer worktable further includes a detection component 4, which includes a laser ruler 41, a light shielding sheet 42, and a photoelectric sensor 43. The laser ruler 41 is mounted on the base 1, the light shielding sheet 42 is mounted on the first slider 21, and the photoelectric sensor 43 is mounted on the base 1. Both the laser ruler 41 and the photoelectric sensor 43 are externally connected to a host computer.

[0085] When in use, the laser ruler 41 is used alone, while the shading sheet 42 is used in conjunction with the photoelectric sensor 43. The laser ruler 41 can detect the displacement of the second slider 23. The shading sheet 42 and the photoelectric sensor 43 can detect the displacement of the first slider 21. Both the laser ruler 41 and the photoelectric sensor 43 are connected to the host computer and can serve as the control basis of the host computer.

[0086] In the technical solution of the above embodiment, the displacement of the second slider 23 is detected by the laser ruler 41, and the displacement of the first slider 21 is detected by the photoelectric sensor 43, so that the repeatability of the wafer worktable can be improved and the adjustment efficiency can be improved.

[0087] In a second aspect, an embodiment of the present application further provides an electron beam detection device, which includes the wafer workpiece stage in any of the above embodiments.

[0088] The electron beam detection equipment provided in the embodiment of the present application has all the beneficial effects of the wafer worktable of the first aspect mentioned above. For details, please refer to the specific description of the wafer worktable in the above embodiment, and this embodiment will not be repeated here.

[0089] Please refer to Figure 7 and Figure 8 , Figure 7 This is a test diagram of the repeatability of the wafer workpiece stage in the related technology; Figure 8 This is a test diagram of the repeatability of the wafer worktable in some embodiments of the present application. The working process of the wafer worktable is described in detail below with a specific embodiment:

[0090] like Figures 3 to 6As shown, the wafer worktable includes a base 1, a drive assembly 2, a bearing 3 and a detection assembly 4. The base 1 includes a bottom plate and a vertical plate. Three bearing columns 11 are fixedly mounted on the bottom plate, and the three bearing columns 11 are located at the three vertices of an equilateral triangle. The drive assembly 2 is mounted on the base 1, and the drive assembly 2 includes a first slider 21, a second slider 23, a servo motor, a ball screw pair, a piezoelectric ceramic 24, a connecting plate 26 and a flexible member 27. The first slider 21 slides with the bottom plate of the base 1 through two first guide rails 12. The servo motor is mounted on the bottom plate and connected to the first slider 21 through a ball screw pair, which can drive the first slider 21 to slide. The second slider 23 slides with the vertical plate through two second guide rails 13, and two third guide rails 212 are mounted on the first slider 21, and the second slider 23 slides with the third guide rail 212. The piezoelectric ceramic 24 is mounted on the second slider 23, and there are four piezoelectric ceramics 24, which are respectively mounted at the four corners of the top of the second slider 23. There are four connecting plates 26 and four flexible parts 27, and the piezoelectric ceramics 24, the connecting plates 26, and the flexible parts 27 correspond to each other. The bearing member 3 includes a mounting plate 31, a suction cup 32, and an isolation plate 33. The mounting plate 31 is mounted on the four connecting plates 26. The suction cup 32 and the isolation plate 33 are both mounted on the mounting plate 31. The isolation plate 33 is located on the outside of the suction cup 32. The isolation plate 33 is provided with an isolation ring 331 on the outside of the suction cup 32. The suction cup 32 is an electrostatic suction cup 32. The mounting plate 31 is provided with an isolation layer on the side (second side) where the suction cup 32 and the isolation plate 33 are installed. The isolation layer can isolate the high-voltage electric field. The isolation plate 33 is provided with a grounding hole 332, and the grounding hole 332 is connected to the grounding wire to suppress the divergence of the high-voltage electric field. The first slider 21 is wrapped around the outside of the servo motor to isolate the interference of the high-voltage electric field on the servo motor. The first slider 21 is used to wrap the wall of the cavity of the servo motor. The magnetic shielding layer can shield the magnetic field formed when the servo motor is running. A protective shell 25 is provided on the outside of the piezoelectric ceramic 24 to provide electric field shielding for the piezoelectric ceramic 24. The detection component 4 includes a laser ruler 41, a light shielding sheet 42 and a photoelectric sensor 43. The laser ruler 41 is mounted on the vertical plate, the photoelectric sensor 43 is mounted on the bottom plate, and the light shielding sheet 42 is mounted on the first slider 21. The light shielding sheet 42 and the first slider 21 slide synchronously.

[0091] An external transmission mechanism (such as a vacuum manipulator) places the wafer on the three supporting columns 11. Under the control of the host computer, the servo motor drives the first slider 21 to slide in the first direction through the ball screw pair, and the first slider 21 drives the second slider 23 to slide in the second direction until the top surface of the suction cup 32 exceeds the top surface of the supporting column 11, and the wafer is adsorbed on the suction cup 32. The host computer adjusts the servo motor based on the feedback of the photoelectric sensor 43 and the laser ruler 41. The servo motor can realize macro-adjustment of the suction cup 32 (such as adjustment of millimeter-level moving distance). In addition, the host computer uses the detection device of the electron beam detection equipment as a basis to realize micro-adjustment of the suction cup 32 (such as adjustment of nanometer-level moving distance) through the piezoelectric ceramic 24, the connecting plate 26 and the flexible member 27, thereby adjusting the working distance between the wafer surface and the electron gun. After the wafer is inspected, the suction cup 32 descends, and the top surface of the suction cup 32 is lower than the top surface of the supporting column 11 , and the wafer is left on the supporting column 11 and is taken away by an external transmission mechanism.

[0092] The carrier 3 of the wafer worktable can be raised and lowered to accommodate electron guns with different working distances and wafers of different thicknesses, thereby reducing unnecessary changes to the wafer worktable caused by electron gun upgrades and iterations. It can also better adapt to different product specifications of different wafer plants and improve versatility. It can also reduce the difficulty of integration and adjustment of the wafer worktable, shorten the production cycle, and improve production efficiency. The drive assembly 2 of the wafer worktable uses a servo motor to directly drive the first slider 21 through a ball screw pair, and relies on the first slider 21 to drive the second slider 23, thereby shortening the transmission path. Compared with related technologies, it is found that when performing high-speed transmission tests, such as Figure 7 As shown in FIG. 1 , the wafer workpiece table support column 11 of the related art is stuck at a speed of 3 mm / s. Figure 8 As shown, the wafer worktable of this embodiment still operates normally at a displacement speed of 30mm / s. After nearly 100,000 reciprocating cycle comparison tests, the top rod connecting rod of the related scheme was deformed, the repeatability accuracy of the wafer worktable exceeded 500μm, while the repeatability accuracy of this wafer worktable was still less than 1μm. The wafer worktable can suppress the divergence of high-voltage electric fields and shield magnetic fields (play an isolation role) by setting an isolation layer, an isolation plate 33, and a magnetic shielding layer, effectively protecting electronic components, and can be successfully used in high-energy electron beam detection equipment.

[0093] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A wafer worktable, characterized in that: include: A base, provided with a plurality of bearing columns, wherein the bearing columns are used for delivering wafers; A driving assembly, mounted on the base, for providing driving force; A carrier is mounted on the driving assembly, the carrier comprising a mounting plate and a suction cup, the first side of the mounting plate is mounted on the driving assembly, the second side of the mounting plate is provided with an isolation layer, the isolation layer is used to isolate the high voltage electric field, the suction cup is mounted on the mounting plate, and is used to slide along the carrier column under the drive of the driving assembly to pick up and place the wafer.

2. The wafer worktable according to claim 1, characterized in that: The bearing member further comprises an isolation plate, the isolation plate is mounted on the mounting plate, the isolation plate is provided with an avoidance hole, the suction cup is located in the avoidance hole, and the outer peripheral surface of the suction cup is connected to the side wall of the avoidance hole; The isolation plate is provided with a grounding hole, and the grounding hole is provided with a grounding wire.

3. The wafer worktable according to claim 2, characterized in that: On the side facing away from the mounting plate, the isolation plate is provided with an isolation ring along the periphery of the avoidance hole; On the side away from the mounting plate, the distance between the surface of the isolation ring and the mounting plate is greater than the distance between the surface of the suction cup and the mounting plate, so that the isolation ring is used to limit the wafer on the suction cup.

4. The wafer worktable according to claim 1, characterized in that: The driving component includes a macro-motion component, and the macro-motion component includes: A first slider, with the direction intersecting with the axis of the bearing column as a first direction, the first slider slidingly cooperates with the base along the first direction, a first inclined surface is provided on the top of the first slider, and the angle between the first inclined surface and the first direction is less than 45°; a driving member, mounted on the base and connected to the first slider, and used for driving the first slider to slide along the first direction; The second slider has a direction parallel to the axis of the supporting column as the second direction. The second slider slides with the base along the second direction. The second slider is connected to the supporting member. A second inclined surface is provided at the bottom of the second slider. The second inclined surface slides with the first inclined surface to drive the suction cup to translate along the second direction.

5. The wafer worktable according to claim 4, characterized in that: The driving component includes a servo motor, which is mounted on the base and located in the cavity of the first slider. The servo motor is connected to a host computer. A magnetic shielding layer is provided on the wall of the cavity. The thickness of the magnetic shielding layer is 0.1 mm to 0.5 mm.

6. The wafer worktable according to claim 4, characterized in that: The base is provided with a first guide rail along the first direction, and the first guide rail is slidably matched with the first sliding block; The base is provided with a second guide rail along the second direction, and the second guide rail is slidably matched with the second slider; Along the first direction, the second guide rail is located at one side of the first guide rail.

7. The wafer worktable according to claim 4, characterized in that: Also included is a detection component, the detection component comprising: A laser ruler, mounted on the base, for detecting the displacement of the second slider; A light shielding sheet, mounted on the first sliding block; A photoelectric sensor, mounted on the base, for cooperating with the light shielding sheet to detect the displacement of the first slider; The laser ruler and the photoelectric sensor are both externally connected to a host computer.

8. The wafer worktable according to claim 4, characterized in that: The driving assembly further includes a micro-motion assembly, and the micro-motion assembly includes: A piezoelectric ceramic is mounted on the second slider and connected to a host computer, and is used for extending and retracting in the second direction; A connecting plate, comprising a first connecting portion, a second connecting portion and a third connecting portion, wherein one end of the second connecting portion is connected to the first connecting portion and the other end is connected to the third connecting portion, the second connecting portion is provided with a weak section at the connection between the first connecting portion and the third connecting portion, the weak section is used to guide deformation between the first connecting portion and the second connecting portion and between the second connecting portion and the third connecting portion, the first connecting portion is connected to the second slider, the second connecting portion is connected to the piezoelectric ceramic, and the third connecting portion is connected to the bearing member; A flexible member, one end of which is connected to the second sliding block, and the other end of which is connected to the third connecting portion, is used to pull the third connecting portion in a direction away from the supporting member.

9. The wafer worktable according to claim 8, characterized in that: A protective shell is provided on the outer side of the piezoelectric ceramic, and the protective shell is used to provide electric field shielding for the piezoelectric ceramic.

10. An electron beam testing device, characterized in that: Comprising the wafer workpiece stage as described in any one of claims 1 to 9.

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