Upper grinding and polishing disc system

Abstract

The present invention provides an upper grinding and polishing disk system, which relates to the field of semiconductor processing technology and includes an upper grinding and polishing disk, a disk body unit, a disk cover unit, a disk core unit, and a connecting sleeve. The upper grinding and polishing disk is fixedly mounted below the disk body unit. The disk cover unit is fixedly connected to the top of the disk body unit, and a cavity is formed between the disk cover unit and the disk body unit. The disk core unit is enclosed in the cavity. One end of the connecting sleeve is used to be fixedly connected to a mounting base, and the other end is fixedly connected to the middle of the disk core unit. The disk core unit includes a first magnetic module, and at least one of the lower surface of the disk cover unit and the upper surface of the disk body unit is provided with a first magnetic element for forming a magnetic match with the first magnetic module. By controlling the magnetic pole direction of the first magnetic module and / or the first magnetic element and the magnetic field strength between the two, the direction and value of the magnetic force applied by the disk core unit to the disk cover unit and the disk body unit can be controlled. This improves the adjustment range of wafer pressure, control accuracy, and grinding and polishing quality.

Description

Technical Field

[0001] The present application relates to the field of semiconductor processing technology, and in particular to an upper grinding and polishing disk system. Background Art

[0002] In the grinding and polishing equipment that completes the processing of multiple semiconductor wafers at a time, the upper grinding and polishing disc is a key component. The diameter of the upper grinding and polishing disc is relatively large, usually around 1000mm, and some exceed 1500mm.

[0003] like Figure 1 、 Figure 2 、 Figure 3 As shown, it is a schematic diagram of the semiconductor wafer grinding and polishing processing equipment of the prior art, which mainly consists of an upper disk part A1, a universal joint A11, an upper disk drive unit A12, a lower disk part B1, a lower disk drive unit B11 and a machine base C1. The upper disk part A1 is driven by the upper disk drive unit A12 through the universal joint A11. The upper disk part A1 can rotate clockwise and counterclockwise and can change speed. The upper disk part A1 has four degrees of freedom and is a floating rotation structure. The lower disk surface of the upper disk part A1 is an upper grinding and polishing disk; the lower disk part B1 is driven by the lower disk drive unit B11 and can rotate clockwise and counterclockwise and can change speed. The lower disk part B1 has only one degree of rotation freedom and is a rigid rotation structure. The upper disk surface of the lower disk part B1 is a lower grinding and polishing disk; between the upper grinding and polishing disk of the upper disk part A1 and the lower grinding and polishing disk of the lower disk part B1 is the planetary wheel part D1, and the planetary wheel contains a wafer D11. The upper grinding and polishing disc, the lower grinding and polishing disc and the planetary wheel rotate separately to achieve grinding or polishing of multiple wafers.

[0004] During the processing, the upper grinding and polishing disk needs to be pressurized when polishing the wafer. In the existing technology, the pressurization method is mainly hydraulic or pneumatic. The strength of the pressurization is achieved by adjusting the pressure (pressure) of the hydraulic or pneumatic pressure. With the continuous improvement of the accuracy and efficiency of wafer grinding and polishing, the accuracy of the pressure provided by the upper grinding and polishing disk to the wafer is also constantly improving.

[0005] When no additional pressure is applied to the upper polishing plate, the weight of the upper polishing plate constitutes the baseline pressure on the wafer. In the prior art, the use of air pressure or hydraulic pressure to apply additional pressure to the upper polishing plate has the following drawbacks:

[0006] The control of downforce is not precise enough to meet the demand;

[0007] The downforce adjustment range is small and cannot meet the working scenarios where the downforce is less than the deadweight;

[0008] Mechanical vibrations caused by hydraulic and pneumatic pressure controls limit the quality of grinding and polishing. Summary of the Invention

[0009] The purpose of this application is to provide an upper grinding and polishing disk system, aiming to solve the problem of how to improve the adjustment range, control accuracy and grinding and polishing quality of wafer pressure in the related art.

[0010] Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

[0011] According to the present application, an upper grinding and polishing disc system is provided, characterized in that it comprises an upper grinding and polishing disc, a disc body unit, a disc cover unit, a disc core unit and a connecting sleeve;

[0012] The upper grinding and polishing disc is fixedly mounted below the disc unit;

[0013] The disc cover unit is fixedly connected to the upper part of the disc body unit, and a cavity is formed between the disc cover unit and the disc body unit;

[0014] The core unit is wrapped in the cavity;

[0015] One end of the connecting sleeve is used to be fixedly connected to a mounting base, and the other end passes through the disk cover unit and is fixedly connected to the middle part of the disk core unit;

[0016] The disk core unit includes a first magnetic module, and at least one of the lower surface of the disk cover unit and the upper surface of the disk body unit is provided with a first magnetic element for forming a magnetic fit with the first magnetic module;

[0017] By controlling the magnetic pole direction of the first magnetic module and / or the first magnetic element and the magnetic field strength between the two, the magnetic force direction and magnetic force value applied by the disk core unit to the disk cover unit and the disk body unit are controlled, thereby controlling the downward pressure value applied by the upper grinding and polishing disk.

[0018] In an exemplary embodiment of the present application, the first magnetic module has upper and lower magnetic poles;

[0019] By control, the magnetic pole direction of the upper magnetic pole of the first magnetic module is opposite to the magnetic pole direction of the first magnetic element on the lower surface of the disk cover unit facing the upper magnetic pole of the first magnetic module; and / or the magnetic pole direction of the lower magnetic pole of the first magnetic module is the same as the magnetic pole direction of the first magnetic element on the upper surface of the disk body unit facing the lower magnetic pole of the first magnetic module.

[0020] In an exemplary embodiment of the present application, the first magnetic module has upper and lower magnetic poles;

[0021] By control, the magnetic pole direction of the upper magnetic pole of the first magnetic module is the same as the magnetic pole direction of the first magnetic element on the lower surface of the disk cover unit facing the upper magnetic pole of the first magnetic module; and / or the magnetic pole direction of the lower magnetic pole of the first magnetic module is opposite to the magnetic pole direction of the first magnetic element on the upper surface of the disk body unit facing the lower magnetic pole of the first magnetic module.

[0022] In an exemplary embodiment of the present application, the first magnetic module is an iron core coil structure, the first magnetic elements of the disk cover unit and the disk body unit are both permanent magnet structures, and the magnetic poles facing the first magnetic module have the same direction;

[0023] The magnetic pole directions of the magnetic poles at both ends of the first magnetic module are changed by controlling the coil current input direction; the magnetic force value applied by the first magnetic module to the magnet of the disk cover unit and / or the magnet of the disk body unit is changed by controlling the coil current size.

[0024] In an exemplary embodiment of the present application, the first magnetic module is an integral modular structure, including an iron core 1, a coil 1, an upper protective cover, and a lower protective cover.

[0025] In an exemplary embodiment of the present application, the iron core 1 is an I-shaped structure, the coil 1 is wound around the waist of the iron core 1, and when the coil 1 is energized, the iron core 1 forms four magnetic poles.

[0026] In an exemplary embodiment of the present application, the disk core unit further includes a disk core body, and the first magnetic modules are multiple groups, the multiple groups of the first magnetic modules are embedded in the disk core body, and the multiple groups of the first magnetic modules are radially distributed on the disk core body from the center of the disk core body;

[0027] The disk cover unit also includes a disk cover body, and the disk body unit also includes a disk body; the first magnetic elements of the disk cover unit and / or the disk body unit are multiple groups, and the multiple groups of first magnetic elements are embedded in the lower surface of the disk cover body and / or the upper surface of the disk body, forming multiple concentric ring structures.

[0028] In an exemplary embodiment of the present application, a motor rotor is fixedly provided on the inner periphery of the disk cover unit, and a motor stator is fixedly provided on the outer periphery of the disk core unit. The motor rotor and the motor stator constitute a motor unit, and the motor unit can drive the disk cover unit and the disk body unit to rotate relative to the disk core unit.

[0029] In an exemplary embodiment of the present application, gaps are provided between the disk core unit and the lower surface of the disk cover unit, the upper surface of the disk body unit, and the peripheral cavity wall of the cavity formed between the disk cover unit and the disk body unit.

[0030] In an exemplary embodiment of the present application, a protruding sleeve is fixedly provided at the center of the core unit, and the protruding sleeve is fixedly connected to the connecting sleeve;

[0031] A centering unit is provided in the raised sleeve, and the centering unit includes a centering shaft and a self-aligning bearing. The centering shaft is arranged along the axial direction of the raised sleeve, and the self-aligning bearing is sleeved on the centering shaft. The inner ring of the self-aligning bearing is fixed to the centering shaft, and the outer ring of the self-aligning bearing can slide up and down in the raised sleeve.

[0032] In an exemplary embodiment of the present application, the centering unit also includes a second magnetic module and a second magnetic element, the second magnetic element is fixedly connected to the centering shaft, and the second magnetic module is fixedly connected to the disk core unit; the second magnetic module and the second magnetic element are a coupling pair, and a gap is provided between the second magnetic module and the second magnetic element.

[0033] In an exemplary embodiment of the present application, the second magnetic module includes an iron core 2 and a coil 2, the second magnetic element is a permanent magnet structure, and when the coil 2 is energized, the second magnetic module and the second magnetic element generate an interaction force, and when the current and voltage parameters during power-on change in magnitude or direction, the direction and magnitude of the force will also change accordingly.

[0034] In an exemplary embodiment of the present application, the disk body is made of non-magnetic material.

[0035] In an exemplary embodiment of the present application, the upper grinding and polishing disc has plasticity; by adjusting the current of each group of the first magnetic modules, and then adjusting the magnitude and direction of the electromagnetic force between the first magnetic module and the first magnetic element, the polishing surface shape of the upper grinding and polishing disc is changed.

[0036] In an exemplary embodiment of the present application,

[0037] The polishing surface type of the upper grinding and polishing disc is obtained by the following formula:

[0038] ,

[0039] in, is the deformation of the center of the polishing surface, is the deformation of the polishing surface caused by the attraction of the first magnetic module, is the deformation of the polishing surface caused by the repulsive force of the first magnetic module.

[0040] In an exemplary embodiment of the present application, the calculation and The method is as follows:

[0041] ,

[0042] ,

[0043] ,

[0044] ,

[0045] ,

[0046] ,

[0047] ,

[0048] Where, is the radius of the polishing surface of the upper grinding and polishing disk, is the distance from the farthest edge of the cross section of the first magnetic element to the center of the polishing surface of the upper grinding and polishing disk, is the distance from the nearest edge of the cross section of the first magnetic element to the center of the polishing surface of the upper grinding and polishing disk, is the bending stiffness, is the elastic modulus of the material, is the thickness of the disc, is the Poisson's ratio of the material, is the pressure on the upper grinding and polishing disc, is the electromagnetic force applied by the first magnetic module to the upper grinding and polishing disk, is the number of coil turns, is the current, is the vacuum permeability, is the air gap thickness, is the cross-sectional area of ​​the magnetic circuit.

[0049] In an exemplary embodiment of the present application, the upper grinding and polishing disc has plasticity; by adjusting the current of each group of the first magnetic modules and / or, and then adjusting the magnitude and direction of the electromagnetic force between the first magnetic module and the first magnetic element, the polishing surface shape of the upper grinding and polishing disc is changed.

[0050] In an exemplary embodiment of the present application, the upper grinding and polishing disc has plasticity; by adjusting the current of each group of the first magnetic modules, and then adjusting the magnitude and direction of the electromagnetic force between the first magnetic module and the first magnetic element, the polishing surface shape of the upper grinding and polishing disc is changed.

[0051] The exemplary embodiments of the present application may have some or all of the following beneficial effects:

[0052] 1. In an upper grinding and polishing disk system provided in an example embodiment of the present application, the disk core unit is connected and fixed to the disk core unit through a connecting sleeve, so that the disk core unit remains relatively fixed to the installation base, and by energizing at least one of the first magnetic module and the first magnetic element, a magnetic field is formed between the first magnetic module and the first magnetic element, and a magnetic force is generated. The magnetism generated by the disk core unit can act on both the disk cover unit and the disk body unit, and can also act on the disk cover unit and the disk body unit at the same time to accurately adjust the pressure generated by the upper grinding and polishing disk on the wafer. Specifically, the first magnetic module can be energized to generate magnetic poles, and the first magnetic element can be set as a permanent magnet; the first magnetic module can also be set as a permanent magnet so that the first magnetic element can be energized to generate magnetic poles; or both can be set as electromagnetic structures that generate magnetic poles when energized. The first magnetic element can be installed on either the disk cover unit or the disk body unit; when the first magnetic element is installed on the disk cover unit, if the first magnetic module generates a magnetic force that attracts the first magnetic element, the magnetic force acting on the disk cover unit at this time is downward, which can increase the pressure of the upper grinding and polishing disk on the wafer; if the first magnetic module generates a magnetic force that repels the first magnetic element, the magnetic force acting on the disk cover unit at this time is upward, which can reduce the pressure of the upper grinding and polishing disk on the wafer. When the first magnetic element is installed on the disk body unit, if the first magnetic module generates a magnetic force that attracts the first magnetic element, the magnetic force acting on the disk body unit at this time is upward, which can reduce the pressure of the upper grinding and polishing disk on the wafer; if the first magnetic module generates a magnetic force that repels the first magnetic element, the magnetic force acting on the disk body unit at this time is downward, which can increase the pressure of the upper grinding and polishing disk on the wafer. Of course, the first magnetic element can also be set as two groups, and the two groups of electromagnetic elements are respectively installed in the disk cover unit and the disk body unit. When the first magnetic module and / or the first magnetic element are energized, the first magnetic module generates a magnetic force with the first magnetic element in the disk cover unit, and also generates a magnetic force with the first magnetic element in the disk body unit. It can be understood that the sum of the weights of the upper grinding and polishing disk, the disk body unit, and the disk cover unit can be used as a reference pressure for generating pressure on the wafer. On this basis, if the pressure required by the wafer is greater than the reference pressure, the magnetic field generated by the first magnetic module and the first magnetic element can increase the pressure on the wafer by causing the upper grinding and polishing disk to be subjected to a downward magnetic force; if the pressure required by the wafer is less than the reference pressure, the magnetic field generated by the first magnetic module and the first magnetic element can reduce the pressure on the wafer by causing the upper grinding and polishing disk to be subjected to an upward magnetic force. In summary, by adjusting the parameters of the input current and / or voltage, the intensity and direction of the magnetic force can be controlled, thereby adjusting the pressure of the upper grinding and polishing disk on the wafer.Compared to the hydraulic or pneumatic methods used in conventional technologies, the magnetic force used in this application eliminates the compressibility and fluidity of gases and liquids, thereby improving the accuracy of pressure control on the wafer. This application can change the direction of the magnetic force on the upper grinding and polishing disk by adjusting the parameters of the input current and / or voltage, thereby increasing or decreasing the pressure on the wafer on the basis of the baseline pressure. This expands the adjustment range of the pressure on the wafer. The magnetic force used in this application also eliminates the mechanical vibrations during the hydraulic and pneumatic control used in conventional technologies, thereby further improving the grinding quality of the wafer.

[0053] 2. In an upper grinding and polishing disc system provided in an example embodiment of the present application, the upper grinding and polishing disc and the disc body are set to be plastic, a plurality of first magnetic modules are set, and they are radially distributed around the center of the disc core body; by adjusting the size and direction of the electromagnetic force generated by the first magnetic module and / or the second magnetic module at different positions, the surface shape of the grinding and polishing disc can be changed, so that the upper grinding and polishing disc can meet different processing requirements.

[0054] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0056] Figure 1 It is a cross-sectional schematic diagram of a semiconductor wafer grinding and polishing processing equipment in the prior art;

[0057] Figure 2 It is a three-dimensional schematic diagram of the lower grinding and polishing equipment in the prior art;

[0058] Figure 3 A three-dimensional schematic diagram of an upper grinding and polishing disc system in the prior art;

[0059] Figure 4 A three-dimensional cross-sectional schematic diagram of a magnetic levitation semiconductor upper grinding and polishing disk system according to an embodiment of the present application is shown;

[0060] Figure 5 A schematic front view of a magnetic levitation semiconductor upper grinding and polishing disk system according to an embodiment of the present application is shown;

[0061] Figure 6A simplified cross-sectional diagram of a magnetic levitation semiconductor upper grinding and polishing disk system according to an embodiment of the present application is shown;

[0062] Figure 7 A cross-sectional schematic diagram of a magnetic levitation semiconductor upper grinding and polishing disk system according to an embodiment of the present application is shown;

[0063] Figure 8 for Figure 7 A partial enlarged schematic diagram of part A;

[0064] Figure 9 for Figure 7 A partial enlarged schematic diagram of part B;

[0065] Figure 10 for Figure 7 A partial enlarged schematic diagram of part C;

[0066] Figure 11 A three-dimensional cross-sectional schematic diagram of a disk core unit in an embodiment of the present application is shown;

[0067] Figure 12 A three-dimensional exploded schematic diagram of a disk core unit in an embodiment of the present application is shown;

[0068] Figure 13 shows a three-dimensional schematic diagram of a magnetic core module 1 in an embodiment of the present application;

[0069] Figure 14 Schematic diagram of an explosion of a magnetic core module 1 in an embodiment of the present application is shown;

[0070] Figure 15 The polishing surface of the polishing disc in the embodiment of the present application is shown in FIG. 、 、 Schematic diagram of the distances referred to.

[0071] Description of reference numerals:

[0072] A1, upper disk part; A11, universal joint; A12, upper disk drive unit; B1, lower disk part; B11, lower disk drive unit; C1, machine base; D1, planetary wheel part; D11, wafer; 1, upper grinding and polishing disk; 2, disk body unit; 3, disk cover unit; 4, disk core unit; 5, centering unit; 6, disk rack; 7, connecting sleeve; 8, first magnetic module; 21, magnetic core one; 22, disk body; 23, sealing ring; 31, magnetic core two; 32, motor rotor; 33, disk cover; 41, motor stator; 42, disk core; 51, centering shaft; 52, self-aligning bearing; 53, second magnetic module; 54, magnetic core three; 55, screw; 71, screw one; 72, screw two; 81, core one; 82, coil one; 83, upper protective cover; 84, lower protective cover. DETAILED DESCRIPTION

[0073] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent like or similar structures, and thus their detailed descriptions will be omitted. Furthermore, the figures are merely schematic illustrations of the present application and are not necessarily drawn to scale.

[0074] While relative terms such as "upper" and "lower" are used in this specification to describe the relationship of one illustrated component to another, these terms are used for convenience only, such as in accordance with the orientation of the illustrations in the accompanying drawings. It should be understood that if the illustrated device were flipped upside down, the component described as "upper" would become the component "lower." When a structure is referred to as "on" another structure, this may mean that the structure is integrally formed with the other structure, that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through the other structure.

[0075] The terms "a", "an", "the" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express open-ended inclusion and mean that additional elements / components / etc. may be present in addition to the listed elements / components / etc.; the terms "first" and "second" are used only as labels and do not limit the quantity of their objects.

[0076] Reference Figure 4 、 Figure 5 and Figure 6 As shown, in an embodiment of the present application, an upper grinding and polishing disc system is provided, including an upper grinding and polishing disc 1, a disc body unit 2, a disc cover unit 3, a disc core unit 4, a centering unit 5, a mounting base, a connecting sleeve 7, a first magnetic module 8 and a multi-channel sensor (not shown in the figure).

[0077] Furthermore, the upper grinding and polishing disc 1 is fixedly mounted below the disc unit 2;

[0078] The disc cover unit 3 is fixedly connected to the upper part of the disc body unit 2, and a cavity is formed between the disc cover unit 3 and the disc body unit 2;

[0079] The core unit 4 is wrapped in the cavity;

[0080] One end 7 of the connecting sleeve is used to be fixedly connected to a mounting base, and the other end passes through the disk cover unit and is fixedly connected to the middle part of the disk core unit. In this application, the mounting base can be regarded as the disk frame 6 shown in the figure, of course, this is not restrictive;

[0081] The disk core unit 4 includes a first magnetic module 8, and at least one of the lower surface of the disk cover unit 3 and the upper surface of the disk body unit 2 is provided with a first magnetic element for forming a magnetic fit with the first magnetic module 8;

[0082] By controlling the magnetic pole direction and magnetic field strength between the first magnetic module 8 and / or the first magnetic element, the direction and magnitude of the magnetic force applied by the core unit 4 to the disk cover unit 3 and disk body unit 2 are controlled, thereby controlling the downward pressure exerted by the upper polishing disk 1. Specifically, when the first magnetic module 8 is configured as an electromagnet, the first magnetic element is configured as a permanent magnet; when the first magnetic module 8 is configured as a permanent magnet, the first magnetic element is configured as an electromagnet. Alternatively, both the first magnetic module 8 and the first magnetic element may be configured as electromagnets. In this application, the preferred embodiment is described using the first magnetic module 8 as an electromagnet and the first magnetic element as a permanent magnet. When power is applied to the first magnetic module 8, it generates a magnetic force. The magnetic poles formed by the first magnetic module 8 can be either the same as (repulsive) or opposite to (attractive) those of the first magnetic element. When power is not applied to the first magnetic module 8, the combined weight of the upper polishing disk 1, disk body unit 2, and disk cover unit 3 acts on the wafer, generating a pressure that serves as a baseline pressure.

[0083] The electromagnetic force generated by the first magnetic module 8 and the first magnetic element to adjust the pressure on the wafer has the following solutions:

[0084] Option 1: The first magnetic element is set in the disk cover unit 3. At this time, the first magnetic element is located above the first magnetic module 8. When the magnetic pole of the first magnetic module 8 facing the first magnetic element is the same as that of the first magnetic element, the first magnetic module 8 generates an attractive force on the first magnetic element. At this time, the electromagnetic force is downward, thereby increasing the pressure of the upper grinding and polishing disk 1 on the wafer; on the contrary, if the magnetic pole of the first magnetic module 8 facing the first magnetic element is opposite, the first magnetic module 8 generates a repulsive force on the first magnetic element. At this time, the electromagnetic force is upward, thereby reducing the pressure of the upper grinding and polishing disk 1 on the wafer.

[0085] Option 2: The first magnetic element is set in the disk unit 2. At this time, the first magnetic element is located below the first magnetic module 8. When the magnetic pole of the first magnetic module 8 facing the first magnetic element is the same as that of the first magnetic element, the first magnetic module 8 generates an attractive force on the first magnetic element. At this time, the electromagnetic force is upward, thereby reducing the pressure of the upper grinding and polishing disk 1 on the wafer; on the contrary, if the magnetic pole of the first magnetic module 8 facing the first magnetic element is opposite, the first magnetic module 8 generates a repulsive force on the first magnetic element. At this time, the electromagnetic force is downward, thereby increasing the pressure of the upper grinding and polishing disk 1 on the wafer.

[0086] Solution three: The first magnetic elements are arranged into two groups, one group of first magnetic elements is arranged in the disk cover unit 3, and the other group of first magnetic elements is arranged in the disk body unit 2, and the first magnetic module 8 is arranged between the two groups of first magnetic elements in the vertical direction. It is worth noting that the ends of the first magnetic elements of the two groups facing the first magnetic module 8 should be of the same magnetic pole. If it is necessary to increase the pressure of the upper grinding and polishing disk 1 on the wafer on the basis of the reference pressure, the bottom of the first magnetic module 8 and the first magnetic element in the disk body unit 2 are of the same magnetic pole, and the top of the first magnetic module 8 and the first magnetic element in the disk cover unit 3 are of the opposite magnetic pole. If it is necessary to reduce the pressure of the upper grinding and polishing disk 1 on the wafer on the basis of the reference pressure, the bottom of the first magnetic module 8 and the first magnetic element in the disk body unit 2 are of the opposite magnetic pole, and the top of the first magnetic module 8 and the first magnetic element in the disk cover unit 3 are of the same magnetic pole.

[0087] Reference Figure 6 As shown, in the embodiment of the present application, solution 3 is adopted as the optimal implementation. In solution 3, the first magnetic element provided in the disk body unit 2 is magnetic core 1 21 , and the first magnetic element provided in the disk cover unit 3 is magnetic core 2 31 .

[0088] In the embodiment of the present application, the disk unit 2 includes a magnetic core 21 and a disk 22, which is a circular pancake structure. The disk cover unit 3 includes a magnetic core 31 and a disk cover 33, which is a circular cover.

[0089] Furthermore, the disk body 22 is made of a non-magnetic material, and its specific material is not limited. Both the first magnetic core 21 and the second magnetic core 31 are provided in multiple groups and are permanent magnets. The first magnetic core 21 is embedded in the disk body 22 and forms a multiple concentric ring structure. The second magnetic core 31 is embedded in the cavity of the disk cover 33 and forms a multiple concentric ring structure on the bottom.

[0090] When the first magnetic module 8 is powered, it generates upper and lower magnetic poles. For example, to increase pressure on a wafer, the upper magnetic pole of the first magnetic module 8 and the magnetic core 2 31 below the disk cover unit 3 have opposite magnetic properties, attracting each other. The lower magnetic pole of the first magnetic module 8 and the magnetic core 1 21 of the disk body unit 2 have the same magnetic properties, repelling each other. Under the magnetic force of magnetic module 1 8, the disk cover unit 3 and disk body unit 2 are forced downward, thereby increasing pressure on the wafer.

[0091] Reference Figure 7 、 Figure 8 and Figure 9 As shown, further, a sealing ring 23 is provided between the circumference of the disc body 22 and the circumference of the disc cover 33 .

[0092] Reference Figure 7 、 Figure 11 and Figure 12 As shown, in the embodiment of the present application, the disk core unit 4 also includes a disk core body 42, the disk core body 42 is a disk structure, the first magnetic modules 8 are multiple groups, and the first magnetic modules 8 are radially distributed on the disk core body 42 from the center of the disk core body 42.

[0093] Reference Figure 12 、 Figure 13 and Figure 14 As shown, further, the first magnetic module 8 is an integral modular structure, including an iron core 81 , a coil 82 , an upper protective cover 83 and a lower protective cover 84 .

[0094] Furthermore, the iron core 1 81 is an I-shaped structure, and the coil 1 82 is wound around the waist of the iron core 1 81 . When the coil 1 82 is energized, four magnetic poles are formed.

[0095] Reference Figure 7 and Figure 10 As shown, in the embodiment of the present application, a protruding sleeve is provided at the center of the disk core unit 4, the protruding sleeve of the disk core unit 4 is fixedly connected to the connecting sleeve 7, the connecting sleeve 7 is fixedly mounted on the disk frame 6, the disk core unit 4 is fixed to the protruding sleeve, and the centering unit 5 is assembled in the protruding sleeve.

[0096] In an embodiment of the present application, the centering unit 5 includes a centering shaft 51 and a self-aligning bearing 52. The centering bearing is arranged in a vertical direction. The self-aligning bearing 52 is sleeved on the centering shaft 51, and the inner ring of the self-aligning bearing 52 is connected and fixed to the centering shaft 51; the self-aligning bearing 52 is installed in the raised sleeve of the disk core unit 4, and the interior of the raised sleeve is set as a center hole. The outer ring of the self-aligning bearing 52 is clearance-fitted with the center hole of the disk core unit 4, and the outer ring of the self-aligning bearing 52 can slide up and down in the center hole of the raised sleeve.

[0097] In the embodiment of the present application, the centering unit 5 is located above the disk body unit 2, the centering shaft 51 is fixedly connected to the disk body 22 by a screw 55, the disk body unit 2 is a disk-shaped structure, the upper grinding and polishing disk 1 is fixedly mounted below the disk body unit 2, the disk cover unit 3 is buckled into the upper part of the disk body unit 2, the disk cover unit 3 is a circular shell structure, the disk cover unit 3 is fixedly connected to the disk body unit 2, the disk cover unit 3 and the disk body unit 2 form a circular cavity, the disk core unit 4 is wrapped in the circular cavity of the disk cover unit 3 and the disk body unit 2, and there are gaps between the disk core unit 4 and the disk cover unit 3 and the disk body unit 2 above and below, and between the circumferences.

[0098] The disc core unit 4 limits two degrees of freedom of the disc body unit 2 and the disc cover unit 3 through the self-aligning bearing 52 and the centering shaft 51, so that the disc body unit 2 and the disc cover unit 3 form a floating rotation structure.

[0099] In an embodiment of the present application, the centering unit 5 also includes a second magnetic module 53 and a magnetic core three 54. The magnetic core three 54 is installed on the top of the centering shaft 51. The magnetic core three 54 is fixedly connected to the centering shaft 51. The outer ring of the magnetic core three 54 is the second magnetic module 53. The second magnetic module 53 is embedded in the raised sleeve of the disk core unit 4 through a screw 71 and a connecting sleeve 7. The second magnetic module 53 is fixedly connected to the disk core unit 4. The second magnetic module 53 and the magnetic core three 54 are a coupling pair, and a gap is provided between the second magnetic module 53 and the magnetic core three 54.

[0100] Furthermore, the second magnetic module 53 includes an iron core 2 and a coil 2, and the magnetic core 3 54 is a permanent magnet structure; when the coil 2 of the second magnetic module 53 is energized, the second magnetic module 53 and the magnetic core 3 54 will generate an interaction force, either upward or downward. When the magnitude or direction of the current and voltage parameters changes, the direction and magnitude of the force will also change accordingly.

[0101] Reference Figure 7 and Figure 8 As shown, a motor rotor 32 is fixed to the inner periphery of the disk cover unit 3, and a motor stator 41 is fixed to the outer periphery of the disk core unit 4. The motor rotor 32 and the motor stator 41 constitute the motor unit. Specifically, the motor stator 41 is fixed to the outer circumferential wall of the disk core unit 4; the motor rotor 32 is fixed to the inner circumferential wall of the disk cover unit 3, and the motor rotor 32 surrounds the outer side of the motor stator 41. A uniform radial gap exists between the motor rotor 32 and the motor stator 41. When the motor stator 41 is energized, the motor rotor 32 rotates due to electromagnetic induction.

[0102] Furthermore, the motor stator 41 includes an iron core 3 and a coil 3, and the coil 3 is wound around the circumferential outer wall of the iron core 3. The motor rotor 32 is a permanent magnet structure.

[0103] Reference Figure 7As shown, in actual application, the motor stator 41 is connected to the driver or inverter and control system via wires. The multi-channel first magnetic module 8 and the second magnetic module 53 are also connected to the power supply and control system via wires. Multiple sensors, including displacement sensors, force sensors, temperature sensors, speed sensors, current and voltage sensors, and liquid and gas pressure and flow sensors, are connected to the control system or CNC system via wires or wirelessly, forming a closed-loop control system. The disk core unit 4 is fixedly connected to the connecting sleeve 7 via screw 1 71, and the connecting sleeve 7 is fixedly connected to the disk holder 6 via screw 2 72. The disk holder 6 can drive the entire magnetic levitation semiconductor upper grinding and polishing disk system to move up and down, or to move and swing, and to separate from the lower polishing disk equipment to facilitate loading and unloading. Furthermore, before grinding and polishing, the disk holder 6 can also drive the magnetic levitation semiconductor upper grinding and polishing disk system to move up and down to determine its initial position.

[0104] Grinding and polishing are two inseparable processes in the wafer grinding process. There are various processing techniques for grinding or polishing. According to the needs of the wafer processing technology, the material, shape or structure of the upper grinding and polishing disc 1 will vary. The upper grinding and polishing disc 1 is fixed on the disc body unit 2. The disc body unit 2 and the disc cover unit 3 and the centering shaft 51 are a fixedly connected integrated structure. The disc body unit 2, the disc cover unit 3 and the centering shaft 51 are centered with the disc core unit 4 through the self-aligning bearing 52. The self-aligning bearing 52 limits the two degrees of freedom of the disc body unit 2, the disc cover unit 3 and the centering shaft 51, which are the up and down degrees of freedom and the rotational degree of freedom, but there is no limit on the two tilting degrees of freedom. Except for the connection between the centering shaft 51 and the self-aligning bearing 52, the disc body unit 2, the disc cover unit 3 and the disc core unit 4 and the circumference have no contact. The disc body unit 2, the disc cover unit 3 and the centering shaft 51 form a rotating and floating structure.

[0105] During operation, the upper grinding and polishing disk 1 is pressed on the wafer. After the motor stator 41 and the motor rotor 32 are energized, the disk cover unit 3, the centering shaft 51, the disk body unit 2 and the upper grinding and polishing disk 1 are driven to rotate together. The weight of the disk cover unit 3, the centering shaft 51, the disk body unit 2 and the upper grinding and polishing disk 1 serves as part of the pressure for grinding or polishing the wafer. When the pressure on the wafer is increased, the other part of the pressure is generated by multiple groups of first magnetic modules 8 and magnetic core 1 21, magnetic core 2 31, and the second magnetic module 53 and magnetic core 3 54.

[0106] like Figure 6As shown, the first magnetic module 8 generates a magnetic field when it is energized. When the magnetic poles of the magnetic field generated by the first magnetic module 8 are opposite to the magnetic poles of the magnetic field of the magnetic core 2 31, the disk cover unit 3 is attracted and the pressure is downward. At the same time, the magnetic poles of the magnetic field generated by the first magnetic module 8 are the same as the magnetic poles of the magnetic field of the magnetic core 1 21, the disk body unit 2 is repelled and the pressure is also downward. At this time, the pressure on the wafer is the resultant force of the weight of the disk cover unit 3, the centering shaft 51, the disk body unit 2, the upper grinding and polishing disk 1 and the magnetic force generated by the first magnetic module 8. The first magnetic module 8 is a plurality of groups of modules, and the resultant force is also the resultant force of the magnetic forces of the plurality of groups of modules of the first magnetic module 8. During operation, the control system can control each first magnetic module 8 in real time, so that the magnetic force generated by each first magnetic module 8 changes according to the pressure required by the wafer.

[0107] The second magnetic module 53 and the magnetic core three 54 can also generate magnetic force. The second magnetic module 53 is also controlled in real time by the control system. The magnetic force it generates also changes according to the pressure required by the wafer. The second magnetic module 53 and the magnetic core three 54 are in the center position.

[0108] In an embodiment of the present application, the upper grinding and polishing disc 1 and the disc body 22 are plastic. When the upper grinding and polishing disc 1 needs to be deformed, that is, when the upper grinding and polishing disc 1 needs to be concave or convex according to the wafer processing process requirements, the control system can control the first magnetic module 8 and / or the second magnetic module 53 to make the first magnetic module 8 and the second magnetic module 53 at different positions adjust accordingly according to the surface shape of the wafer, so that the surface shape of the upper grinding and polishing disc 1 changes to meet the requirements.

[0109] Figure 7 、 Figure 11 、 Figure 12 As shown, the first magnetic modules 8 are radially distributed from the center of the disk core body 42 and arranged on the entire disk surface of the disk core body 42. The second magnetic module 53 is arranged directly above the center of the upper grinding and polishing disk 1 and the disk body 22. When the upper grinding and polishing disk 1 needs to locally change the pressure, the control system can easily achieve it by separately controlling the first magnetic module 8 and / or the second magnetic module 53 in different areas.

[0110] In the embodiment of the present application, there are three ways to adjust the polishing surface of the upper grinding and polishing disk 1 according to the target polishing process requirements, and the specific ways are as follows:

[0111] Method 1: Adjust the current, voltage or a combination of parameters input to each group of first magnetic modules 8 as needed to adjust the electromagnetic intensity and direction of the first magnetic modules 8;

[0112] Method 2: Adjust the current, voltage, or a combination thereof input to the second magnetic module 53 as needed to adjust the electromagnetic intensity and direction of the second magnetic module 53, so that the centering shaft 51 drives the upper grinding and polishing plate 1 to move upward (the polishing surface is concave) or downward (the polishing surface is convex);

[0113] Method 3: Adjust the current, voltage, or a combination of these parameters input to each set of first magnetic modules 8 and second magnetic modules 53 as needed. The first magnetic modules 8 and second magnetic modules 53 are used in concert to apply different electromagnetic forces (the electromagnetic forces can be of different directions or magnitudes) to different locations on the upper grinding and polishing plate 1, thereby changing the surface shape of the upper grinding and polishing plate 1 to achieve a concave or convex surface.

[0114] In some feasible embodiments, the upper grinding and polishing disc 1 provided in the present application can adjust the polishing surface type of the polishing disc by adjusting the magnetic force between the first magnetic module 8 and the magnetic core 1 21 and the magnetic core 2 31. For example, in the actual polishing process, the polishing surface types include a plane, a curved surface with concave inward and convex outward, and a curved surface with convex inward and concave outward. In order to adapt to different polishing processes, the polishing end face needs to be adjusted, and the degree of concave inward and convex outward or convex inward and concave outward can be different, so as to have a variety of polishing surface types based on concave inward and convex outward or convex inward and concave outward. In addition, it should be noted that the polishing end face is a curved surface with concave inward and convex outward, which means that the middle part of the polishing end face is concave inward, and the other parts are at a certain inclination angle with the horizontal plane. The polishing end face is a curved surface with convex inward and concave outward, which means that the middle part of the polishing end face is convex outward, and the other parts are at a certain inclination angle with the horizontal plane.

[0115] Reference Figure 15 As shown, the principle of adjusting the polishing surface shape by the first magnetic module 8 is:

[0116] ,

[0117] ,

[0118] ,

[0119] ,

[0120] in, The deformation of the center of the polished surface (which can be converted into the deformation of the outermost edge of the polished surface), The polished surface is deformed by the attraction of the first magnetic module 8. The polished surface is deformed by the repulsive force of the first magnetic module 8, such as Figure 15 As shown, is the radius of the polished surface, is the distance from the farthest edge of the cross section of the first magnetic module 8 to the center of the polished surface, is the distance from the nearest edge of the cross section of the first magnetic module 8 to the center of the polished surface, is the bending stiffness, is the elastic modulus of the material, is the thickness of the disc 22, is the Poisson's ratio of the material.

[0121] It should be noted that in this application, there are multiple groups of first magnetic elements, and the multiple groups of first magnetic elements are in a ring structure. When calculating the change in the polishing surface shape, the pressure exerted by each group of first magnetic elements on the upper grinding and polishing disc 1 should be calculated separately. Refers to calculating the distance from the farthest edge of the cross section of the first magnetic element in the group to the center of the polished surface, It is the distance from the nearest edge of the cross section of the first magnetic element in the group to the center of the polishing surface.

[0122] The pressure exerted by each first magnetic element on the upper grinding and polishing plate 1 is calculated as follows:

[0123] ,

[0124] ,

[0125] ,

[0126] in, is the pressure on the upper grinding and polishing disc 1, is the electromagnetic force applied by the first magnetic module 8 to the upper grinding and polishing disc 1, is the number of coil turns: In a coil, the more turns there are, the greater the magnetic field strength generated is generally. Current: The magnitude of the current will also affect the strength of the magnetic field. The greater the current, the stronger the magnetic field. is the vacuum permeability: This is a physical constant that describes the properties of the magnetic field in a vacuum. Air gap thickness: In devices such as electromagnets, the air gap thickness affects the distribution of the magnetic field and the magnitude of the electromagnetic force; Magnetic circuit cross-sectional area: The magnetic circuit cross-sectional area will also affect the electromagnetic force. The larger the cross-sectional area, the greater the electromagnetic force may be under the same conditions.

[0127] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the embodiments of the present invention. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not covered by this application. The specification and embodiments are intended to be exemplary only, and the true scope and spirit of the present invention are indicated by the appended claims.

Claims

1. An upper grinding and polishing disc system, characterized in that: It includes an upper grinding and polishing disc, a disc body unit, a disc cover unit, a disc core unit and a connecting sleeve; The upper grinding and polishing disc is fixedly mounted below the disc unit; The disc cover unit is fixedly connected to the upper part of the disc body unit, and a cavity is formed between the disc cover unit and the disc body unit; The core unit is wrapped in the cavity; One end of the connecting sleeve is used to be fixedly connected to a mounting base, and the other end passes through the disk cover unit and is fixedly connected to the middle part of the disk core unit; The disk core unit includes a first magnetic module, and at least one of the lower surface of the disk cover unit and the upper surface of the disk body unit is provided with a first magnetic element for forming a magnetic fit with the first magnetic module; By controlling the magnetic pole direction of the first magnetic module and / or the first magnetic element and the magnetic field strength therebetween, the direction and value of the magnetic force applied by the disk core unit to the disk cover unit and the disk body unit are controlled, thereby controlling the downward pressure applied by the upper grinding and polishing disk; The disk core unit further includes a disk core body, the first magnetic modules are multiple groups, the multiple groups of the first magnetic modules are embedded in the disk core body, and the multiple groups of the first magnetic modules are radially distributed on the disk core body from the center of the disk core body; The disk cover unit further includes a disk cover body, and the disk body unit further includes a disk body; the first magnetic elements of the disk cover unit and / or the disk body unit are multiple groups, and the multiple groups of first magnetic elements are embedded on the lower surface of the disk cover body and / or the upper surface of the disk body, forming a plurality of concentric ring structures; A raised sleeve is fixedly provided at the center of the core unit, and the raised sleeve is fixedly connected to the connecting sleeve; A centering unit is provided in the raised sleeve, and the centering unit includes a centering shaft and a self-aligning bearing. The centering shaft is arranged along the axis direction of the raised sleeve, and the self-aligning bearing is sleeved on the centering shaft. The inner ring of the self-aligning bearing is fixed to the centering shaft, and the outer ring of the self-aligning bearing can slide up and down in the raised sleeve; The centering unit also includes a second magnetic module and a second magnetic element. The second magnetic element is fixedly connected to the centering shaft, and the second magnetic module is fixedly connected to the disk core unit. The second magnetic module and the second magnetic element form a coupling pair, and a gap is provided between the second magnetic module and the second magnetic element.

2. The upper grinding and polishing disc system according to claim 1, characterized in that: The first magnetic module has upper and lower magnetic poles; By control, the magnetic pole direction of the upper magnetic pole of the first magnetic module is opposite to the magnetic pole direction of the first magnetic element on the lower surface of the disk cover unit facing the upper magnetic pole of the first magnetic module; and / or the magnetic pole direction of the lower magnetic pole of the first magnetic module is the same as the magnetic pole direction of the first magnetic element on the upper surface of the disk body unit facing the lower magnetic pole of the first magnetic module.

3. The upper grinding and polishing disc system according to claim 1, characterized in that: The first magnetic module has upper and lower magnetic poles; By control, the magnetic pole direction of the upper magnetic pole of the first magnetic module is the same as the magnetic pole direction of the first magnetic element on the lower surface of the disk cover unit facing the upper magnetic pole of the first magnetic module; and / or the magnetic pole direction of the lower magnetic pole of the first magnetic module is opposite to the magnetic pole direction of the first magnetic element on the upper surface of the disk body unit facing the lower magnetic pole of the first magnetic module.

4. The upper grinding and polishing disc system according to claim 2 or 3, characterized in that: The first magnetic module is an iron core coil structure, and the first magnetic elements of the disk cover unit and the disk body unit are both permanent magnet structures, and the magnetic poles facing the first magnetic module have the same direction; The magnetic pole directions of the magnetic poles at both ends of the first magnetic module are changed by controlling the coil current input direction; the magnetic force value applied by the first magnetic module to the magnet of the disk cover unit and / or the magnet of the disk body unit is changed by controlling the coil current size.

5. The upper grinding and polishing disc system according to claim 4, characterized in that: The first magnetic module is an integral modular structure, including an iron core 1, a coil 1, an upper protective cover and a lower protective cover.

6. The upper grinding and polishing disc system according to claim 5, characterized in that: The iron core 1 is an I-shaped structure, and the coil 1 is wound around the waist of the iron core 1. When the coil 1 is energized, the iron core 1 forms four magnetic poles.

7. The upper grinding and polishing disc system according to claim 1, characterized in that: A motor rotor is fixedly provided on the inner periphery of the disk cover unit, and a motor stator is fixedly provided on the outer periphery of the disk core unit. The motor rotor and the motor stator constitute a motor unit, and the motor unit can drive the disk cover unit and the disk body unit to rotate relative to the disk core unit.

8. The upper grinding and polishing disc system according to claim 1, characterized in that: Gaps are provided between the disk core unit and the lower surface of the disk cover unit, the upper surface of the disk body unit, and the peripheral cavity wall of the cavity formed between the disk cover unit and the disk body unit.

9. The upper grinding and polishing disc system according to claim 1, characterized in that: The second magnetic module includes an iron core 2 and a coil 2. The second magnetic element is a permanent magnet structure. When the coil 2 is energized, the second magnetic module and the second magnetic element generate an interaction force. When the current and voltage parameters during power-on change in magnitude or direction, the direction and magnitude of the force will also change accordingly.

10. The upper grinding and polishing disc system according to claim 1, characterized in that: The disk body is made of non-magnetic conductive material.

11. The upper grinding and polishing disc system according to claim 1, characterized in that: The upper grinding and polishing disc has plasticity; by adjusting the current of each group of the first magnetic modules, the magnitude and direction of the electromagnetic force between the first magnetic modules and the first magnetic element are adjusted, so that the polishing surface shape of the upper grinding and polishing disc changes.

12. The upper grinding and polishing disc system according to claim 4, characterized in that: The polishing surface type of the upper grinding and polishing disc is obtained by the following formula: , in, is the deformation of the center of the polishing surface, is the deformation of the polishing surface caused by the attraction of the first magnetic module, It is the deformation amount of the polishing surface of the upper grinding and polishing plate caused by the repulsive force of the first magnetic module.

13. The upper grinding and polishing disc system according to claim 9, characterized in that: The upper grinding and polishing disc has plasticity; by adjusting the current of each group of the first magnetic module and / or the second magnetic module, the magnitude and direction of the electromagnetic force between the first magnetic module and the first magnetic element, as well as the magnitude and direction of the electromagnetic force between the second magnetic module and the second magnetic element are adjusted, so that the polishing surface shape of the upper grinding and polishing disc changes.

14. The upper grinding and polishing disc system according to claim 9, characterized in that: The upper grinding and polishing disc has plasticity; by adjusting the current of the second magnetic module, the magnitude and direction of the electromagnetic force between the second magnetic module and the second magnetic element are adjusted, so that the polishing surface shape of the upper grinding and polishing disc changes.

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