A high-precision leveling device, leveling platform, and leveling method

Abstract

The present application provides a high-precision leveling device, a leveling platform, and a leveling method, which belong to the field of high-precision leveling technology. In view of the problem of how to reduce the control difficulty and operating cost of the active leveling mechanism when the leveling device has a high-precision leveling function, the present application provides a high-precision leveling device, including a drive assembly and a transmission assembly. Based on the ball screw and the rigid support, the rotation stroke of the ball screw can be converted into a displacement on the height of the support surface of the rigid support. Through the stretching assembly, the return clearance between the rigid support and the ball screw is eliminated to ensure the support stability after the rigid support is in place; and multiple displacement detection devices are used to achieve precise monitoring of the displacement of the rigid support; thereby, by adopting a mechanical transmission type active leveling solution, the stability and reliability after leveling are guaranteed, and at the same time, various measures are taken to eliminate errors in the mechanical transmission process to ensure the adjustment accuracy of the leveling device.

Description

Technical Field

[0001] The present application relates to the technical field of lithography equipment, and in particular to a high-precision leveling device, a leveling platform, and a leveling method. Background Art

[0002] High-precision leveling technology plays an important role in many fields, and high-precision leveling mechanisms are widely used in various fields. For example, in optical equipment, the imaging quality of the microscope is directly affected by its leveling accuracy; in the semiconductor manufacturing process, key processes such as lithography and etching have extremely high requirements for the leveling accuracy of the equipment. In the precision assembly process of the electronics, automobile and other industries, high-precision leveling technology can ensure the accurate assembly of parts, reduce assembly errors, and improve the overall performance of the product; in the aerospace field, the attitude control of the aircraft also has extremely high requirements for leveling accuracy.

[0003] At the same time, leveling technology can be divided into passive leveling and active leveling. Passive leveling has the disadvantages of slow response speed, low leveling accuracy and high latency, while active leveling can achieve fast and high-precision leveling.

[0004] Among them, most active leveling mechanisms are often driven by voice coil motors, which are directly driven by drivers without intermediate transmission links such as gears and belts, thereby reducing energy loss and mechanical friction and improving the overall efficiency of the system. Voice coil motors are also characterized by high precision (the precision can reach micrometers or even nanometers), high response speed, high acceleration, smooth movement, high reliability and easy control. Therefore, active leveling mechanisms using voice coil motors are widely used in the field of high-precision leveling technology, for example, the leveling process of silicon wafers in the field of photolithography technology.

[0005] However, voice coil motors also have the problem of poor stability in leveling results, which can easily cause drift, resulting in a poor final leveling result. In order to achieve the high-precision leveling effect of the voice coil motor, an extremely complex control system is required to adjust and control the voice coil motor at a high frequency, which makes the control cost of the voice coil motor in the field of high-precision leveling extremely high. Summary of the invention

[0006] The purpose of the present application is to solve the problem of how to reduce the control difficulty and operation cost of the active leveling mechanism in the prior art when the leveling device has a high-precision leveling function. Therefore, the present application provides a high-precision leveling device, which is based on a ball screw and a rigid support, converts the rotation stroke of the ball screw into the displacement of the height of the support surface of the rigid support, and ensures the accuracy of the ball screw rotation process through the couplings at both ends of the ball screw, eliminates the return clearance between the rigid support and the ball screw through the stretching assembly, ensures the accuracy and controllability of the displacement of the rigid support, and can ensure the support stability after the rigid support is in place; further, multiple displacement detection devices are used to achieve accurate monitoring of the displacement of the rigid support; thus, by adopting a mechanical transmission type active leveling solution, the stability and reliability after leveling are guaranteed, and at the same time, the errors in the mechanical transmission process are eliminated through a variety of measures to ensure the adjustment accuracy of the leveling device.

[0007] The embodiment of the present application provides a high-precision leveling device, comprising:

[0008] A leveling base plate, a transmission assembly and a driving assembly; the driving assembly is connected to the leveling base plate through the transmission assembly and adjusts the height of the leveling base plate;

[0009] The driving assembly includes a rigid base and a ball screw arranged on the rigid base along a first direction;

[0010] One end of the ball screw is connected to a driving member via a coupling, and the other end is provided with a first displacement detection unit via a coupling;

[0011] The ball screw is movably provided with a rigid support member, and the rigid support member includes a driving portion cooperating with the ball screw and a supporting surface facing away from the driving portion;

[0012] A stretching assembly is provided at one end of the rigid support member, and the stretching assembly is used to apply a pre-tightening force along a first direction to the rigid support member;

[0013] The driving member drives the ball screw to rotate and drives the rigid support member to move in a first direction, and the support height of the support surface of the rigid support member in the first direction changes continuously;

[0014] A second displacement detection unit and a third displacement detection unit are respectively provided on both sides of the ball screw;

[0015] The first displacement detection unit detects the displacement of the rigid support member in a first direction according to the rotation of the ball screw;

[0016] The second displacement detection unit is used to detect the limit position of the rigid support member on the ball screw in the first direction;

[0017] The third displacement detection unit is used to detect the zero-position in-place state of the rigid support member.

[0018] By adopting the above technical solution, the transmission connection between the ball screw and the rigid support can convert the rotation process of the ball screw into the displacement of the rigid support along the first direction. At the same time, due to the change in the height of the support surface in the first direction, the support height in the same vertical direction can be changed by the displacement of the rigid support in the first direction. The displacement adjustment with preliminary accuracy can be achieved by setting the transmission ratio, and a stretching component is provided to apply a pre-tightening force to the rigid support along the first direction; thereby ensuring that the ball screw and the rigid support maintain continuous contact, eliminating the return clearance during the transmission process, and further improving the adjustment accuracy of the leveling device.

[0019] In addition, the first displacement detection unit detects the displacement of the rigid support member in the first direction, the second displacement detection unit detects the limit position of the rigid support member on the ball screw in the first direction, and the third displacement detection unit detects the zero position in place state of the rigid support member. Thus, the displacement of the rigid support member in the whole process can be detected and corrected multiple times, ensuring the accuracy of the displacement detection of the rigid support member, so as to improve the high controllability and high precision of the adjustment process of the leveling device.

[0020] In some embodiments, the transmission assembly is in contact with the support surface, and the transmission assembly is fixedly arranged relative to the base in the horizontal direction and movably arranged in the height direction;

[0021] The transmission assembly includes a connecting member and an abutment wheel rotatably disposed on the connecting member; and the transmission assembly is abutted and connected with the support surface through the abutment wheel;

[0022] A leaf spring is arranged on the side of the connecting member facing away from the abutting wheel, and the transmission assembly is fixedly arranged on the leveling base plate through the connecting member and the leaf spring.

[0023] In some embodiments, the drive assembly further comprises a frame assembly disposed around the base;

[0024] The frame assembly includes a bottom frame, an upper frame, and a side frame connecting the bottom frame and the upper frame;

[0025] The base is fixedly connected to the bottom frame and is connected to an external object through the bottom frame;

[0026] The upper frame is located above the supporting surface and is provided with a through space corresponding to the abutment wheel;

[0027] A limiting structure is provided between the upper frame and the connecting piece of the transmission assembly, and the movement of the transmission assembly relative to the base in the horizontal direction is limited by the limiting structure.

[0028] In some embodiments, the second displacement detection unit is configured as two proximity switches spaced apart along the first direction;

[0029] The third displacement detection unit is configured as a photoelectric position sensor;

[0030] The rigid support member is configured as a wedge-shaped structure, and the inclined surface of the wedge-shaped structure is configured as the support surface.

[0031] In some embodiments, the leveling device further comprises:

[0032] A leveling component, the leveling component comprising a light source, a first optical path module, a second optical path module and a sensing device;

[0033] The leveling substrate is provided with an optical path reflection area, the detection light emitted by the light source is gathered to the optical path reflection area through the first optical path module, and the second optical path module receives the reflected light from the optical path reflection area and focuses it to the sensing device;

[0034] The sensing device determines the posture of the leveling substrate according to the change of the detected reflected light.

[0035] In some embodiments, the first optical path module includes a first incident lens, a transmitting end reflector, and a second incident lens sequentially arranged along the optical path direction; wherein the first incident lens and the second incident lens are both convex lenses;

[0036] The second optical path module comprises a second reflecting lens, a receiving end reflecting mirror and a first reflecting lens which are sequentially arranged along the optical path direction; wherein both the first reflecting lens and the second reflecting lens are convex lenses.

[0037] In some embodiments, a control unit is further included, wherein the control unit is connected to the first displacement detection unit, the second displacement detection unit, the third displacement detection unit, the sensing device and the driving member;

[0038] The control process of the control unit includes:

[0039] According to the signals of the first displacement detection unit, the second displacement detection unit and the third displacement detection unit, controlling the driving member to drive the rigid support member to the zero position in place state;

[0040] The sensing device is used to determine whether the posture of the leveling substrate meets the leveling accuracy requirement. If not, the driving component is controlled to perform leveling compensation until the posture of the leveling substrate meets the leveling accuracy requirement.

[0041] The present application also provides a high-precision leveling platform, comprising: at least three leveling devices as described in the above embodiments;

[0042] The at least three leveling devices are centrally symmetrically distributed and have a symmetry center, and share the same leveling substrate and leveling inspection component.

[0043] In some embodiments, the leveling platform further comprises a horizontal motion platform and a control unit, the at least three leveling devices are mounted on the horizontal motion platform; and the control unit is simultaneously connected to the at least three leveling devices;

[0044] The leveling substrate is provided with suction cups corresponding to the symmetry centers of at least three leveling devices, and the suction cups are adsorbed with a base;

[0045] The light path reflection area is arranged on the substrate.

[0046] The present application also provides a leveling method, including the leveling platform as described in the above embodiment, and the specific steps include:

[0047] S1, loading the substrate into the control unit;

[0048] S2, controlling the horizontal motion platform to move, and moving the optical path reflection area to an area detectable by the leveling component;

[0049] S3, performing leveling measurement to obtain the inclination of the leveling device relative to the symmetry center;

[0050] S4, judging whether the posture of the leveling substrate meets the leveling accuracy requirement according to the sensing device, and if the posture of the leveling substrate meets the leveling accuracy requirement, maintaining the state of the leveling device;

[0051] S5. If not, control each leveling device to perform leveling compensation; and repeat steps S3 to S5 until the posture of the leveling substrate meets the leveling accuracy requirement.

[0052] Other features and corresponding beneficial effects of the present application are described in the latter part of the specification, and it should be understood that at least some of the beneficial effects become obvious from the records in the specification of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 A schematic diagram of the structure of a leveling device provided in an embodiment of the present application;

[0054] Figure 2 A top view of the structure of a driving assembly of a leveling device provided in an embodiment of the present application;

[0055] Figure 3 A structural side view of a driving assembly of a leveling device provided in an embodiment of the present application;

[0056] Figure 4 A schematic structural diagram of a side frame and an upper frame in a frame assembly of a leveling device provided in an embodiment of the present application;

[0057] Figure 5 A schematic diagram of the structure of a transmission assembly of a leveling device provided in an embodiment of the present application when it cooperates with a support surface;

[0058] Figure 6 A schematic diagram of the structure of an adjustment platform provided in an embodiment of the present application;

[0059] Figure 7 A top view of the structure of an adjustment platform provided in an embodiment of the present application;

[0060] Figure 8 A schematic diagram of the structure of a leaf spring of a transmission assembly of a leveling device provided in an embodiment of the present application;

[0061] Fig. 9 A flow chart of specific steps of a leveling method provided in an embodiment of the present application;

[0062] Fig.10 A simplified schematic diagram of the leveling principle of a leveling method provided in an embodiment of the present application.

[0063] Description of reference numerals:

[0064] 1. Horizontal motion platform;

[0065] 3. Level the substrate;

[0066] 4. Light source;

[0067] 5. Sensing device;

[0068] 13. First incident lens; 14. Transmitting end reflector; 15. Second incident lens; 16. First reflector lens; 17. Receiving end reflector; 18. Second reflector lens;

[0069] 7. Control unit;

[0070] 8. Drive control assembly; 8-1. First displacement detection unit; 8-2. Base; 8-3. Coupling; 8-4. Mounting plate; 8-5. Ball screw; 8-6. Driving member; 8-7. Stretching assembly; 8-8. Second displacement detection unit; 8-9. Third displacement detection unit; 8-10. Wedge; 8-11. First side frame; 8-12. Second side frame; 8-13. Upper frame; 8-14. Bottom frame;

[0071] 9. Transmission components;

[0072] 9-1, leaf spring; 9-2, first fixing hole; 9-3, avoidance hole; 9-4, through hole; 9-5, second fixing hole; 9-6, third fixing hole; 9-9, connecting piece;

[0073] 10. Suction cup;

[0074] 11. Base. DETAILED DESCRIPTION

[0075] The following specific embodiments illustrate the implementation of the present application, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this application are limited to the implementation. On the contrary, the purpose of introducing the application in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide a deep understanding of the present application, the following description will include many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0076] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0077] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0078] In the description of the present application, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description created by the present application, unless otherwise specified, "multiple" means two or more.

[0079] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0080] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0081] See also Figure 1 to Figure 10 , Figure 1 A schematic diagram of the structure of a leveling device provided in an embodiment of the present application is shown in FIG. Figure 2 A top view of the structure of a driving assembly of a leveling device provided in an embodiment of the present application, Figure 3 A structural side view of a driving assembly of a leveling device provided in an embodiment of the present application, Figure 4 A schematic diagram of the structure of a side frame and an upper frame in a frame assembly of a leveling device provided in an embodiment of the present application, Figure 5 This is a schematic diagram of the structure of a transmission assembly of a leveling device provided in an embodiment of the present application when it cooperates with a support surface. Figure 6 A schematic diagram of the structure of a tuning platform provided in an embodiment of the present application is shown in FIG. Figure 7 A top view of the structure of an adjustment platform provided in an embodiment of the present application, Figure 8 A schematic diagram of the structure of a leaf spring of a transmission assembly of a leveling device provided in an embodiment of the present application, Fig. 9 A flow chart of specific steps of a leveling method provided in an embodiment of the present application is provided. Fig.10A simplified schematic diagram of the leveling principle of a leveling method provided in an embodiment of the present application.

[0082] like Figures 1 to 10 As shown, the embodiment of the present application provides a high-precision leveling device, comprising:

[0083] A leveling substrate 3, a transmission assembly 9 and a driving assembly 8; the driving assembly 8 is connected to the leveling substrate 3 through the transmission assembly 9, and adjusts the height of the leveling substrate 3;

[0084] The driving assembly 8 includes a rigid base 8-2 and a ball screw 8-5 disposed on the rigid base 8-2 along a first direction;

[0085] One end of the ball screw 8-5 is connected to a driving member 8-6 via a coupling 8-3, and the other end is provided with a first displacement detection unit 8-1 via the coupling 8-3;

[0086] The ball screw 8-5 is movably provided with a rigid support member, which includes a driving portion cooperating with the ball screw 8-5 and a supporting surface facing away from the driving portion;

[0087] A stretching assembly 8-7 is provided at one end of the rigid support member, and the stretching assembly 8-7 is used to apply a pre-tightening force along a first direction to the rigid support member;

[0088] The driving member 8-6 drives the ball screw 8-5 to rotate and drives the rigid support member to move in the first direction, and the support height of the support surface of the rigid support member in the first direction changes continuously;

[0089] A second displacement detection unit 8-8 and a third displacement detection unit 8-9 are respectively provided on both sides of the ball screw 8-5;

[0090] The first displacement detection unit 8-1 detects the displacement of the rigid support member in the first direction according to the rotation of the ball screw 8-5;

[0091] The second displacement detection unit 8-8 is used to detect the limit position of the rigid support member on the ball screw 8-5 in the first direction;

[0092] The third displacement detection unit 8-9 is used for the zero-position in-place state of the rigid support member.

[0093] Among them, the main function of the ball screw 8-5 is to convert rotational motion into linear motion, and it has very small friction resistance, is not easy to wear, and has extremely high reliability and adjustment accuracy.

[0094] In one embodiment, the ball screw 8-5 is mainly composed of a screw, a nut, a ball, a pre-compression plate, a reverser, a dust collector, etc. The ball rolls between the screw and the nut, converting the sliding friction into rolling friction, thereby greatly reducing the friction and improving the transmission efficiency.

[0095] In one embodiment, the ball screw 8 - 5 has extremely high adjustment accuracy and can achieve micron or nanometer positioning accuracy.

[0096] It should be noted that in the extremely high-precision adjustment requirements, it is necessary to ensure the reliability and high precision of each link of the leveling device. Among them, the main part lies in the accuracy of displacement adjustment and the precise monitoring of the displacement process.

[0097] Therefore, by adopting the above technical solution, the transmission connection between the ball screw 8-5 and the rigid support can convert the rotation process of the ball screw 8-5 into the displacement of the rigid support along the first direction. At the same time, due to the change in the height of the support surface in the first direction, the support height in the same vertical direction can be changed by the displacement of the rigid support in the first direction. The displacement adjustment with preliminary accuracy can be achieved by setting the transmission ratio.

[0098] At the same time, it should be noted that due to the matching processing error between the ball screw 8-5 and the rigid support member, when the ball screw 8-5 drives the rigid support member to move to a certain position, a slight return displacement will be generated, resulting in a decrease in the displacement accuracy adjustment. Therefore, the embodiment of the present application is provided with a stretching assembly 8-7 for applying a pre-tightening force along the first direction to the rigid support member; thereby ensuring continuous fit between the ball screw 8-5 and the rigid support member, eliminating the return gap during the transmission process, and further improving the adjustment accuracy of the leveling device.

[0099] Furthermore, the driving member 8-6 of the ball screw 8-5 is located at one end of the ball screw 8-5, and it is difficult to ensure the smoothness of the rotation process of the ball screw 8-5 away from the driving member 8-6. Therefore, the two ends of the ball screw 8-5 are set on the base 8-2 through the coupling 8-3 to ensure the stability of the rotation process of the ball screw 8-5.

[0100] In addition, the first displacement detection unit 8-1 detects the displacement of the rigid support member in the first direction, the second displacement detection unit 8-8 detects the limit position of the rigid support member on the ball screw 8-5 in the first direction, and the third displacement detection unit 8-9 detects the zero position in place state of the rigid support member. Thus, the displacement of the rigid support member in the whole process can be detected and corrected multiple times, ensuring the accuracy of the displacement detection of the rigid support member, so as to improve the high controllability and high precision of the adjustment process of the leveling device.

[0101] In one embodiment, the transmission assembly 9 is in contact with the support surface, and the transmission assembly 9 is fixedly arranged in the horizontal direction relative to the base 8-2, and is movably arranged in the height direction;

[0102] The transmission assembly 9 includes a connecting member and an abutment wheel rotatably arranged on the connecting member; and the transmission assembly 9 is abutted and connected with the support surface through the abutment wheel;

[0103] A leaf spring is arranged on the side of the connecting member facing away from the abutting wheel, and the transmission assembly 9 is fixed to the leveling base plate 3 through the connecting member and the leaf spring.

[0104] By adopting the above technical solution, the consistency of the connection between the transmission component 9 and the leveling substrate 3 can be guaranteed to a great extent, ensuring that the transmission component 9 can move synchronously with the leveling substrate 3.

[0105] It should be noted that, since the support surface has a height change in the first direction, a horizontal component force is easily formed when the support surface supports the transmission assembly 9, thereby affecting the stability and reliability of the transmission assembly 9 in the vertical direction.

[0106] Therefore, in one embodiment, the drive assembly 8 further includes a frame assembly disposed around the base 8 - 2 ;

[0107] The frame assembly includes a bottom frame 8-14, an upper frame 8-13, and a side frame connecting the bottom frame 8-14 and the upper frame 8-13; wherein the side frame includes a first side frame 8-11 and a second side frame 8-12 arranged opposite to each other;

[0108] The base 8-2 is fixedly connected to the bottom frame 8-14, and is connected to an external object through the bottom frame 8-14;

[0109] The upper frame 8-13 is located above the support surface and is provided with a through space corresponding to the abutment wheel;

[0110] A limiting structure is provided between the upper frame 8-13 and the connecting piece of the transmission assembly 9, and the movement of the transmission assembly 9 in the horizontal direction relative to the base 8-2 is limited by the limiting structure.

[0111] By limiting the horizontal movement of the transmission component 9 relative to the base 8-2 through the limiting structure, the stability and reliability of the vertical movement of the transmission component 9 can be ensured, and the horizontal component force caused by the supporting force of the supporting surface can be balanced.

[0112] Furthermore, it should be noted that the leveling substrate 3 itself has a relatively high levelness, but due to the extremely high precision requirements of the photolithography technology, even a very small levelness change can easily affect the entire photolithography effect. Therefore, the leveling height range of the leveling device is not large.

[0113] At the same time, during the leveling process of the transmission assembly 9, the force is transmitted to the connecting member 9-9 through the abutment wheel, and then the connecting member 9-9 drives the leveling base plate 3 to form a precise displacement in height; therefore, the roundness of the abutment wheel is very likely to affect the continuity of the change in height range of the leveling base plate 3. As a result, the abutment wheel cannot bear excessive pressure, and the leveling base plate 3 needs to bear the base 11 and maintain a very high level, so its rigidity is very high; as a result, if the leveling base plate 3 directly acts on the connecting member 9-9 and the abutment wheel, it is easy to cause excessive load on the abutment wheel.

[0114] Therefore, in the embodiment of the present application, the connecting member 9-9 is also connected to the leaf spring 9-1. When the leveling base 3 causes excessive pressure on the connecting member 9-9, the connecting member 9-9 itself will deform and transfer the deformation to the leaf spring 9-1, thereby absorbing the deformation and buffering, thereby preventing the abutment wheel from being subjected to excessive pressure and causing permanent deformation.

[0115] In one embodiment, the leaf spring 9-1 includes a first fixing hole 9-2, an avoidance hole 9-3, a through hole 9-4, a second fixing hole 9-5, and a third fixing hole 9-6;

[0116] The leaf spring 9-1 is connected to the connecting member 9-9 through the first fixing hole 9-2; the avoidance hole 9-3 corresponds to the connection between the connecting member 9-9 and the leveling base plate 3, and is used to avoid the fastener (for example, nut) at the connection.

[0117] The leaf spring 9-1 is connected to the leveling base plate 3 through the second fixing hole 9-5 and the third fixing hole 9-6. The through hole 9-4 is used to facilitate operation of the fixing screws below the leaf spring 9-1.

[0118] In one embodiment, the limiting structure adopts a positioning hole set on the upper frame 8-13 and a positioning pin of a connecting piece fixedly set on the transmission assembly 9; the positioning hole is set in the vertical direction and slidably cooperates with the positioning pin to limit the movement of the positioning pin in the horizontal direction.

[0119] In one embodiment, the second displacement detection unit 8-8 is configured as two proximity switches arranged at intervals along the first direction; it should be noted that the limited position of the rigid support member does not require extremely high precision, but the reliability and safety of its detection need to be guaranteed. Therefore, the proximity switch can quickly determine whether the displacement of the rigid support member exceeds the limited position, and it is easy to ensure the high reliability and stability of the components, thereby reducing the detection cost; on the other hand, the proximity switch can directly respond according to the displacement of the rigid support member, thereby improving the response speed and enhancing the safety and reliability of the leveling device.

[0120] The third displacement detection unit 8-9 is configured as a photoelectric position sensor to ensure high accuracy in detecting the zero-position in-position state of the rigid support member.

[0121] The rigid support member is configured as a wedge-shaped structure, and the inclined surface of the wedge-shaped structure is configured as a support surface.

[0122] In one embodiment, the rigid support member includes a mounting plate 8-4 fixed to the ball screw 8-5 and a wedge 8-10 mounted on the mounting plate 8-4. Separate manufacturing can make the rigidity and hardness of the wedge 8-10 greater than the rigidity and hardness of the mounting plate 8-4, reducing the manufacturing cost of the rigid support member.

[0123] In one embodiment, the leveling device further comprises:

[0124] A leveling component, the leveling component comprises a light source 4, a first optical path module, a second optical path module and a sensing device 5;

[0125] The leveling substrate 3 is provided with an optical path reflection area, the detection light emitted by the light source 4 is gathered to the optical path reflection area through the first optical path module, and the second optical path module receives the reflected light from the optical path reflection area and focuses it to the sensing device 5;

[0126] The sensing device 5 determines the posture of the leveling substrate 3 according to the change of the detected reflected light.

[0127] By adopting the above technical solution, it is possible to directly obtain whether the posture of the leveling substrate 3 meets the leveling requirement through the sensing device 5, which is conducive to controlling the leveling device to perform adjustment.

[0128] In one embodiment, the first optical path module includes a first incident lens 13, a transmitting end reflector 14, and a second incident lens 15 which are sequentially arranged along the optical path direction; wherein the first incident lens 13 and the second incident lens 15 are both convex lenses;

[0129] The second optical path module comprises a second reflecting lens 18, a receiving end reflecting mirror 17 and a first reflecting lens 16 which are sequentially arranged along the optical path direction; wherein the first reflecting lens 16 and the second reflecting lens 18 are both convex lenses.

[0130] In one embodiment, it further includes a control unit 7, which is connected to the first displacement detection unit 8-1, the second displacement detection unit 8-8, the third displacement detection unit 8-9, the sensing device 5 and the driving member 8-6;

[0131] The control process of the control unit 7 includes:

[0132] According to the signals of the first displacement detection unit 8-1, the second displacement detection unit 8-8 and the third displacement detection unit 8-9, the driving member 8-6 is controlled to drive the rigid support member to the zero position in place state;

[0133] The sensing device 5 is used to determine whether the posture of the leveling substrate 3 meets the leveling accuracy requirement. If not, the driving member 8 - 6 is controlled to perform leveling compensation until the posture of the leveling substrate 3 meets the leveling accuracy requirement.

[0134] It should be noted that the position change of a single leveling device is entirely dependent on mechanical transmission. Therefore, the position adjustment accuracy of a single leveling device is easily affected by the error of mechanical processing, which makes it difficult for a single leveling device to ensure ultra-high precision continuous change during the displacement change process. For example, when the adjustment accuracy of a single leveling device is 1μm, the single leveling device can stay at +1μm, +2μm, +3μm and +4μm; and when the leveling device has an error, it may actually only be able to stay at +1μm, +1.5μm, +3μm and +4μm.

[0135] Therefore, the present application also provides a high-precision leveling platform, comprising: at least three leveling devices as described in the above embodiments;

[0136] At least three leveling devices are centrally symmetrically distributed and have a symmetry center, and share the same leveling substrate 3 and leveling inspection component.

[0137] Among them, the leveling platform adopts at least three leveling devices, which can ensure that at least three leveling devices can stably support the same leveling substrate 3, and when the leveling device at a single position cannot perform accurate leveling compensation due to errors, the remaining leveling devices can be adjusted synchronously, thereby further increasing the leveling accuracy of the leveling platform through comprehensive adjustment. The leveling accuracy of the leveling platform is further higher than the adjustment accuracy of a single leveling device.

[0138] In one embodiment, the leveling platform further comprises a horizontal motion platform 1 and a control unit 7, at least three leveling devices are mounted on the horizontal motion platform 1; and the control unit 7 is simultaneously connected to at least three leveling devices;

[0139] The leveling substrate 3 is provided with a suction cup 10 corresponding to the symmetric center of at least three leveling devices, and the suction cup 10 is adsorbed with a base 11;

[0140] The light path reflection area is disposed on the substrate 11 .

[0141] In one embodiment, at least three leveling devices are provided in only three, thereby reducing the number of control components that need to be controlled and reducing the control difficulty, thereby reducing the control difficulty and control cost of the leveling platform while ensuring the adjustment accuracy.

[0142] In a usage scenario, the platform can be leveled according to the following leveling method, and the specific steps include:

[0143] S1, control the horizontal motion platform 1 to move, and move the optical path reflection area to the area detectable by the leveling component;

[0144] S2, performing leveling measurement to obtain the tilt of the leveling device relative to the symmetry center;

[0145] S3, judging whether the posture of the leveling substrate 3 meets the leveling accuracy requirement according to the sensing device 5, and if the posture of the leveling substrate 3 meets the leveling accuracy requirement, maintaining the state of the leveling device;

[0146] S4. If not, control each leveling device to perform leveling compensation; and repeat steps S2 to S3 until the posture of the leveling substrate 3 meets the leveling accuracy requirement.

[0147] like Fig. 9 As shown,

[0148] In a leveling process, three leveling devices are marked as ZT1, ZT2, and ZT3 respectively. The detection light emitted by the light source 4 of the leveling component is gathered to the measurement point position of the optical path reflection area through the first optical path module. The center of gravity position shown in the figure is the light beam measurement point position of the leveling component. Through the measurement of the leveling component, the sensing device 5 determines the posture of the leveling substrate 3 according to the change of the detected reflected light. If the leveling accuracy requirement is not met, the tilt direction of the leveling substrate 3 and the tilt amount of the center of gravity position can be judged according to the detection result of the reflected light. According to the tilt direction, the control unit 7 controls the corresponding leveling device to perform vertical adjustment.

[0149] In one embodiment, the posture adjustment of the leveling substrate 3 is performed by controlling variables, that is, two points of the three leveling devices ( ZT1 , ZT2 , and ZT3 ) are fixed, and only one of them is driven for adjustment.

[0150] In a leveling scenario, if ZT1 needs to be adjusted and compensated according to the judgment result of the leveling component. Fig.10 The following is the adjustment model of ZT1. The other two leveling devices (ZT2 and ZT3) are fixed, and the change in the center of gravity is 1 / 3 of the drive amount of ZT1. For example, if the change in the center of gravity is +30um, the drive amount of ZT1 is +90um.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A high-precision leveling device, characterized in that: include: A leveling base plate, a transmission assembly and a driving assembly; the driving assembly is connected to the leveling base plate through the transmission assembly and adjusts the height of the leveling base plate; The driving assembly includes a rigid base and a ball screw arranged on the rigid base along a first direction; One end of the ball screw is connected to a driving member via a coupling, and the other end is provided with a first displacement detection unit via a coupling; The ball screw is movably provided with a rigid support member, and the rigid support member includes a driving portion cooperating with the ball screw and a supporting surface facing away from the driving portion; A stretching assembly is provided at one end of the rigid support member, and the stretching assembly is used to apply a pre-tightening force along a first direction to the rigid support member; The driving member drives the ball screw to rotate and drives the rigid support member to move in a first direction, and the support height of the support surface of the rigid support member in the first direction changes continuously; A second displacement detection unit and a third displacement detection unit are respectively provided on both sides of the ball screw; The first displacement detection unit detects the displacement of the rigid support member in a first direction according to the rotation of the ball screw; The second displacement detection unit is used to detect the limit position of the rigid support member on the ball screw in the first direction; The third displacement detection unit is used to detect the zero position in place state of the rigid support member; The transmission assembly is in contact with the support surface, and the transmission assembly is fixedly arranged in the horizontal direction relative to the base and movably arranged in the height direction; The transmission assembly includes a connecting member and an abutment wheel rotatably disposed on the connecting member; and the transmission assembly is abutted and connected with the support surface through the abutment wheel; A leaf spring is arranged on the side of the connecting member facing away from the abutting wheel, and the transmission assembly is fixedly arranged on the leveling base plate through the connecting member and the leaf spring.

2. The high-precision leveling device according to claim 1, characterized in that: The drive assembly also includes a frame assembly disposed around the base; The frame assembly includes a bottom frame, an upper frame, and a side frame connecting the bottom frame and the upper frame; The base is fixedly connected to the bottom frame and is connected to an external object through the bottom frame; The upper frame is located above the supporting surface and is provided with a through space corresponding to the abutment wheel; A limiting structure is provided between the upper frame and the connecting piece of the transmission assembly, and the movement of the transmission assembly relative to the base in the horizontal direction is limited by the limiting structure.

3. The high-precision leveling device according to claim 1, characterized in that: The second displacement detection unit is configured as two proximity switches spaced apart along the first direction; The third displacement detection unit is configured as a photoelectric position sensor; The rigid support member is configured as a wedge-shaped structure, and the inclined surface of the wedge-shaped structure is configured as the support surface.

4. The high-precision leveling device according to claim 1, characterized in that: Also includes: A leveling component, the leveling component comprising a light source, a first optical path module, a second optical path module and a sensing device; The leveling substrate is provided with an optical path reflection area, the detection light emitted by the light source is gathered to the optical path reflection area through the first optical path module, and the second optical path module receives the reflected light from the optical path reflection area and focuses it to the sensing device; The sensing device determines the posture of the leveling substrate according to the change of the detected reflected light.

5. The high-precision leveling device according to claim 4, characterized in that: The first optical path module comprises a first incident lens, a transmitting end reflector and a second incident lens which are sequentially arranged along the optical path direction; wherein the first incident lens and the second incident lens are both convex lenses; The second optical path module comprises a second reflecting lens, a receiving end reflecting mirror and a first reflecting lens which are sequentially arranged along the optical path direction; wherein both the first reflecting lens and the second reflecting lens are convex lenses.

6. The high-precision leveling device according to claim 4, characterized in that: It also includes a control unit, which is connected to the first displacement detection unit, the second displacement detection unit, the third displacement detection unit, the sensing device and the driving member; The control process of the control unit includes: According to the signals of the first displacement detection unit, the second displacement detection unit and the third displacement detection unit, controlling the driving member to drive the rigid support member to the zero position in place state; The sensing device is used to determine whether the posture of the leveling substrate meets the leveling accuracy requirement. If not, the driving component is controlled to perform leveling compensation until the posture of the leveling substrate meets the leveling accuracy requirement.

7. A high-precision adjustment platform, characterized in that: include: At least three leveling devices according to claim 5 or 6; The at least three leveling devices are centrally symmetrically distributed and have a symmetry center, and share the same leveling substrate and leveling inspection component.

8. The adjustment platform according to claim 7, characterized in that: It also includes a horizontal motion platform and a control unit, wherein the at least three leveling devices are installed on the horizontal motion platform; and the control unit is simultaneously connected to the at least three leveling devices and the horizontal motion platform; The leveling substrate is provided with suction cups corresponding to the symmetry centers of at least three leveling devices, and the suction cups are adsorbed with a base; The light path reflection area is arranged on the substrate.

9. A leveling method, characterized in that: The method comprises the adjustment platform as claimed in claim 8, wherein the specific steps include: S1, controlling the horizontal motion platform to move, and moving the optical path reflection area to an area detectable by the leveling component; S2. Performing leveling measurement to obtain the inclination of the leveling device relative to the symmetry center; S3, judging whether the posture of the leveling substrate meets the leveling accuracy requirement according to the sensing device, and if the posture of the leveling substrate meets the leveling accuracy requirement, maintaining the state of the leveling device; S4. If not, control each leveling device to perform leveling compensation; and repeat steps S2 to S3 until the posture of the leveling substrate meets the leveling accuracy requirement.

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