Polishing device

Abstract

The invention relates to a polishing device. The polishing device comprises a polishing table, and a polishing pad is arranged on the polishing table; the polishing assembly comprises a polishing head and a polishing driving part, the polishing head is used for adsorbing and fixing the wafer, and the polishing driving part is in driving connection with the polishing head to drive the polishing head to drive the wafer to move along the surface of the polishing pad; the trimmer comprises a trimming head and a trimming driving part, and the trimming driving part is in driving connection with the trimming head so as to drive the trimming head to move along the surface of the polishing pad; wherein in the process that the polishing head and the finishing head move along the surface of the polishing pad, the distance between the center position of the polishing head and the center position of the finishing head is larger than the sum of the radius of the polishing head and the radius of the finishing head.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor processing equipment, and in particular to a polishing device. Background Art

[0002] In the semiconductor manufacturing process, chemical mechanical polishing (CMP) is a better process to achieve global planarization. Especially after the semiconductor manufacturing process enters the sub-micron field, chemical mechanical polishing has become an indispensable process technology.

[0003] During the chemical mechanical polishing process, the wafer is adsorbed on the polishing head and in contact with the polishing pad. The polishing platform drives the polishing pad to rotate around the center of the circle, and the polishing head drives the wafer to reciprocate relative to the polishing pad, so that the polishing pad grinds the polishing head. At the same time, the polishing pad is polished with a dresser to remove the grinding residue on the surface of the polishing pad and repair the shape of the grooves on the surface of the polishing pad. Since the movement range of the polishing head and the dresser is between the edge and the center of the polishing pad, the movement range of the two overlaps, so collision accidents are prone to occur, which has an adverse effect on production efficiency. Summary of the invention

[0004] Based on this, it is necessary to provide a polishing device that can avoid collision accidents between the polishing head and the dresser, thereby improving production efficiency, in order to address the above problems.

[0005] A polishing device, comprising:

[0006] A polishing table, wherein a polishing pad is arranged on the polishing table;

[0007] A polishing assembly, comprising a polishing head and a polishing drive, wherein the polishing head is used to absorb and fix the wafer, and the polishing drive is connected to the polishing head to drive the polishing head to drive the wafer to move along the surface of the polishing pad; and

[0008] A dresser, comprising a dresser head and a dresser drive, wherein the dresser drive is drivingly connected to the dresser head to drive the dresser head to move along the surface of the polishing pad;

[0009] Wherein, when the polishing head and the dressing head move along the surface of the polishing pad respectively, the following conditions are satisfied: the distance between the center position of the polishing head and the center position of the dressing head is greater than the sum of the radius of the polishing head and the radius of the dressing head.

[0010] In some embodiments, the polishing head includes a first polishing head and a second polishing head. The first polishing head and the second polishing head are driven by the polishing drive to reciprocate synchronously along a first preset straight line trajectory and a second preset straight line trajectory, respectively. The first preset straight line trajectory and the second preset straight line trajectory both extend from the center of the polishing pad to the edge, and the first preset straight line trajectory and the second preset straight line trajectory are collinear.

[0011] In some embodiments, driven by the dressing drive, the dressing head reciprocates around a fulcrum O between the center and the edge of the polishing pad.

[0012] In some embodiments, when the first polishing head and the dressing head move along the surface of the polishing pad respectively, the following conditions are satisfied:

[0013]

[0014] Wherein, R represents the distance between the fulcrum and the center position of the dressing head, t represents time, w(t) represents the angular velocity of the dressing head swinging around the fulcrum, v1(t) represents the velocity of the first polishing head, and x head1 represents the X-axis coordinate of the center position of the first polishing head at the initial time in a coordinate system with the fulcrum as the origin, the X-axis parallel to the first preset straight line trajectory, and the Y-axis perpendicular to the first preset straight line trajectory, y head1 represents the Y-axis coordinate of the center position of the first polishing head at the initial time in a coordinate system with the fulcrum as the origin, the X-axis parallel to the first preset straight line trajectory, and the Y-axis perpendicular to the first preset straight line trajectory, θ1 represents the angle between the line between the center position of the dressing head and the fulcrum and the X-axis when the dressing head moves to the center of the polishing pad, R pc represents the radius of the trimming head, R head1 represents the radius of the first polishing head.

[0015] In some embodiments, when the second polishing head and the dressing head move along the surface of the polishing pad:

[0016]

[0017] Wherein, R represents the distance between the fulcrum and the center position of the dressing head, t represents time, w(t) represents the angular velocity of the dressing head swinging around the fulcrum, v2(t) represents the velocity of the second polishing head, and x head2 represents the X-axis coordinate of the center position of the second polishing head at the initial time in a coordinate system with the fulcrum as the origin, the X-axis parallel to the second preset linear trajectory, and the Y-axis perpendicular to the second preset linear trajectory, y head2represents the Y-axis coordinate of the center position of the second polishing head at the initial time in a coordinate system with the fulcrum as the origin, the X-axis parallel to the second preset linear trajectory, and the Y-axis perpendicular to the second preset linear trajectory, θ1 represents the angle between the line between the center position of the dressing head and the fulcrum and the X-axis when the dressing head moves to the center of the polishing pad, R pc represents the radius of the trimming head, R head2 represents the radius of the second polishing head.

[0018] In some embodiments, during the swinging process of the dressing head from the edge of the polishing pad to the center of the circle, the angular velocity of the dressing head is accelerated to a maximum positive value Wmax, and then decelerated from the maximum positive value Wmax to 0;

[0019] During the swinging of the dressing head from the center to the edge of the polishing pad, the angular velocity of the dressing head is accelerated from 0 to a negative maximum value -Wmax, and then decelerated from the negative maximum value -Wmax to 0.

[0020] In some embodiments, the angular velocity of the trimming head in the first swing cycle of the reciprocating swing motion satisfies:

[0021] Wherein, T1 represents the time point of 1 / 2 cycle, T2 represents the time point of one cycle, and θ represents the angle value of the dressing head swinging from the edge of the polishing pad to the center of the circle.

[0022] In some embodiments, during the movement of the first polishing head from the edge of the polishing pad to the center of the circle, the speed of the first polishing head is accelerated from 0 to a positive maximum value Vmax, and then decelerated from the positive maximum value Vmax to 0;

[0023] When the first polishing head moves from the center to the edge of the polishing pad, the speed of the first polishing head is accelerated from 0 to a negative maximum value -Vmax, and then decelerated from the negative maximum value -Vmax to 0.

[0024] In some embodiments, the speed of the first polishing head in the first reciprocating movement cycle satisfies:

[0025] Among them, when the first polishing head is in the initial position, the center position of the first polishing head is located at the midpoint of the first preset straight line trajectory, t1 represents the time point of 1 / 4 cycle, t2 represents the time point of 1 / 2 cycle, t3 represents the time point of 3 / 4 cycle, t4 represents the time point of one cycle, and a represents the minimum distance value between the first polishing head and the center of the polishing pad when it is in the initial position.

[0026] In some embodiments, during the movement of the second polishing head from the edge of the polishing pad to the center of the circle, the speed of the second polishing head is accelerated from 0 to a negative maximum value -Vmax, and then decelerated from the negative maximum value -Vmax to 0;

[0027] When the second polishing head moves from the center to the edge of the polishing pad, the angular velocity of the second polishing head is accelerated from 0 to a positive maximum value Vmax, and then decelerated from the positive maximum value Vmax to 0.

[0028] In one embodiment, the speed of the second polishing head in the first movement cycle of the reciprocating movement satisfies:

[0029] Among them, when the second polishing head is in the initial position, the center point of the second polishing head is located at the midpoint of the second preset straight line trajectory, t1 represents the time point of 1 / 4 cycle, t2 represents the time point of 1 / 2 cycle, t3 represents the time point of 3 / 4 cycle, t4 represents the time point of one cycle, and a represents the minimum distance value between the second polishing head and the center of the polishing pad when it is in the initial position.

[0030] The above-mentioned polishing device, when the above-mentioned polishing device is actually used, the polishing table drives the polishing pad to rotate around its own center of circle, the wafer is loaded onto the polishing head, and the polishing drive drives the polishing head to move until the wafer on it abuts against the polishing pad, and drives the wafer to move along the surface of the polishing pad, so that the polishing pad performs chemical mechanical polishing on the wafer. At the same time, the trimming head of the trimming drive also moves along the surface of the polishing pad, so that the trimming head trims the surface of the polishing pad. Since the distance between the center position of the polishing head and the center position of the trimming head (i.e., the center distance between the polishing head and the trimming head) is always greater than the sum of the radius of the polishing head and the radius of the trimming head during the movement of the polishing head and the trimming head respectively along the surface of the polishing pad, it is ensured that the polishing head and the trimming head will never collide, that is, it is ensured that there will be no collision accident between the two, thereby avoiding adverse effects on production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic structural diagram of a polishing device in one embodiment of the present application;

[0032] Figure 2 for Figure 1 A demonstration diagram showing the movement process of the dressing head, the first polishing head and the second polishing head in the polishing device shown;

[0033] Figure 3 for Figure 2 The variation curve of the swing angular velocity w(t) of the trimming head with time shown in FIG.

[0034] Figure 4 for Figure 2The curve of the movement speed v1(t) of the first polishing head as a function of time is shown in FIG.

[0035] Figure 5 for Figure 2 FIG. 5 is a curve showing a change in the moving speed v2(t) of the second polishing head over time. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0037] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0039] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0041] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0042] See also Figure 1 The present application provides a polishing device, including a polishing table 10, a polishing assembly 20 and a dresser 30. A polishing pad 11 is arranged on the polishing table 10, and the polishing table 10 can drive the polishing pad 11 to rotate around the center of a circle. The polishing assembly 20 includes a polishing head and a polishing drive. The polishing head is used to adsorb and fix the wafer, and the polishing drive is connected to the polishing head to drive the polishing head to move relative to the polishing pad 11, thereby driving the wafer to move along the surface of the polishing pad 11, so that the polishing pad 11 performs chemical mechanical polishing on the wafer on the polishing head. The dresser 30 includes a dresser head 31 and a dresser drive, and the dresser drive is connected to the dresser head 31 to drive the dresser head 31 to move along the surface of the polishing pad 11, so that the dresser head 31 dresses the surface of the polishing pad 11. In the process of the polishing head and the dresser head 31 moving along the surface of the polishing pad 11 respectively, it is satisfied that: the distance between the center position of the polishing head and the center position of the dresser head 31 is greater than the sum of the radius of the polishing head and the radius of the dresser head 31.

[0043] Thus, when the above-mentioned polishing device is actually used, the polishing table 10 drives the polishing pad 11 to rotate around its own center of circle, the wafer is loaded onto the polishing head, and the polishing drive drives the polishing head to move until the wafer on it abuts against the polishing pad 11, and drives the wafer to move along the surface of the polishing pad 11, so that the polishing pad 11 performs chemical mechanical polishing on the wafer. At the same time, the trimming head 31 of the trimming drive also moves along the surface of the polishing pad 11, so that the trimming head 31 trims the surface of the polishing pad 11. Since the distance between the center position of the polishing head and the center position of the trimming head 31 (i.e., the center distance between the polishing head and the trimming head 31) is always greater than the sum of the radius of the polishing head and the radius of the trimming head 31 during the movement of the polishing head and the trimming head 31 respectively along the surface of the polishing pad 11, it is ensured that the polishing head and the trimming head 31 will never collide, that is, it is ensured that there will be no collision accident between the two, thereby avoiding adverse effects on production efficiency.

[0044] In the embodiment of the present application, there are two polishing heads, namely a first polishing head 21 and a second polishing head 22. The first polishing head 21 and the second polishing head 22 are driven by the polishing drive to reciprocate synchronously along a first preset linear trajectory and a second preset linear trajectory respectively. The first preset linear trajectory and the second preset linear trajectory both extend from the center of the polishing pad 11 to the edge, and the first preset linear trajectory and the second preset linear trajectory are collinear. Figure 2 In the illustrated embodiment, the first polishing head 21 and the second polishing head 22 are respectively arranged on the left and right sides of the center of the polishing pad 11, and move synchronously in the left and right directions, that is, when the first polishing head 21 moves to the center of the polishing pad 11, the second polishing head 22 moves to the right edge of the polishing pad 11; when the first polishing head 21 moves to the left edge of the polishing pad 11, the second polishing head 22 moves to the center of the polishing pad 11.

[0045] It should be noted that the first polishing head 21 moves to the center of the polishing pad 11 when the right edge of the first polishing head 21 reaches the center of the polishing pad 11. Similarly, the second polishing head 22 moves to the center of the polishing pad 11 when the left edge of the second polishing head 22 reaches the center of the polishing pad 11.

[0046] The first polishing head 21 moves to the edge of the polishing pad 11, which means that the left edge of the first polishing head 21 reaches the left edge of the polishing end; similarly, the second polishing head 22 moves to the edge of the polishing pad 11, which means that the right edge of the second polishing head 22 reaches the right edge of the polishing pad 11.

[0047] Specifically in the embodiment, the polishing drive member can be a mobile motor, that is, the mobile motor is used to drive the first polishing head 21 and the second polishing head 22 to move synchronously. The polishing device also includes a controller, which is communicatively connected to the mobile motor, so that the controller controls the movement of the first polishing head 21 and the second polishing head 22 through the mobile motor, that is, the controller controls the acceleration, deceleration and maximum speed of the first polishing head 21 and the second polishing head 22 through the mobile motor. Optionally, the controller can be an industrial computer, etc.

[0048] In some embodiments, driven by the dressing drive, the dressing head 31 swings back and forth around a fulcrum O between the center and the edge of the polishing pad 11 , thereby dressing the entire surface of the polishing pad 11 .

[0049] Specific to Figure 2 In the illustrated embodiment, the dressing head 31 reciprocates between the upper left edge and the center of the polishing pad 11 around the fulcrum O. The trimming head 31 reaching the edge of the polishing pad 11 means that the upper left edge of the trimming head 31 reaches the upper left edge of the polishing pad 11. The trimming head 31 reaching the center of the polishing pad 11 means that the lower edge of the trimming head 31 reaches the center of the polishing pad 11.

[0050] Specifically in the embodiment, the trimming driving member can be a rotary motor, that is, the rotary motor is used to drive the trimming head 31 to swing around the fulcrum O. The controller is communicatively connected with the rotary motor, so that the controller controls the trimming head 31 to swing around the fulcrum O through the rotary motor, that is, the controller controls the acceleration, deceleration and maximum angular velocity of the trimming head 31 through the rotary motor.

[0051] Specifically in the embodiment, a coordinate system is established with the fulcrum O as the center, the X axis is parallel to the first preset linear trajectory, and the Y axis is perpendicular to the first preset linear trajectory. The coordinates of the center position of the trimming head 31 are (x pc ,y pc ), the coordinates of the center position of the first polishing head 21 are (x1, y head1 ), the coordinates of the center position of the second polishing head 22 are (x2, y head2 ). See Figure 2 As shown, y head1 remain unchanged, y head2 Remain unchanged.

[0052] It can be understood that the distance between the center position of the dressing head 31 and the center position of the first polishing head 21 (ie, the center distance between the two) is:

[0053]

[0054] Wherein, R represents the distance between the fulcrum O and the center position of the dressing head 31, t represents the time, w(t) represents the angular velocity of the dressing head 31 swinging around the fulcrum O, v1(t) represents the moving speed of the first polishing head 21, and x head1 represents the X-axis coordinate of the center position of the first polishing head 21 at the initial time, y head1 represents the Y-axis coordinate of the center position of the first polishing head 21 at the beginning, and θ1 represents the angle between the line between the center position of the dressing head 31 and the fulcrum O and the X-axis when the dressing head 31 moves to the center of the polishing pad 11 .

[0055] In order to ensure that the trimming head 31 and the first polishing head 21 do not collide with each other when they move along the surface of the polishing pad 11, it is necessary to satisfy that the center distance between the trimming head 31 and the first polishing head 21 is greater than the sum of the radii of the two, that is, to satisfy the following formula:

[0056]

[0057] Among them, R pc represents the radius of the dressing head 31, R head1 represents the radius of the first polishing head 21 .

[0058] It can also be understood that the distance between the center position of the dressing head 31 and the center position of the second polishing head 22 (i.e., the center distance between the two) is:

[0059]

[0060] Wherein, R represents the distance between the fulcrum O and the center position of the dressing head 31, t represents the time, w(t) represents the angular velocity of the dressing head 31 swinging around the fulcrum O, v2(t) represents the moving speed of the second polishing head 22, and x head2 represents the X-axis coordinate of the center position of the second polishing head 22 at the initial time, y head2 represents the Y-axis coordinate of the center position of the second polishing head 22 at the beginning, and θ1 represents the angle between the line between the center position of the dressing head 31 and the fulcrum O and the X-axis when the dressing head 31 moves to the center of the polishing pad 11 .

[0061] In order to ensure that the trimming head 31 and the second polishing head 22 do not collide with each other when they move along the surface of the polishing pad 11, it is necessary to satisfy that the center distance between the trimming head 31 and the second polishing head 22 is greater than the sum of the radii of the two, that is, to satisfy the following formula:

[0062]

[0063] Among them, R pc represents the radius of the dressing head 31, R head2 represents the radius of the second polishing head 22 .

[0064] See also Figure 3 As shown, in some embodiments, when the dressing head 31 swings from the edge of the polishing pad 11 to the center of the circle, the angular velocity of the dressing head 31 accelerates from 0 to the positive maximum value Wmax, swings at the positive maximum value Wmax for a certain period of time, and then decelerates from the positive maximum value Wmax to 0.

[0065] When the trimming head 31 swings from the center to the edge of the polishing pad 11, the angular velocity of the trimming head 31 accelerates from 0 to the negative maximum value -Wmax, swings at the negative maximum value -Wmax for a moving time, and then decelerates from the negative maximum value -Wmax to 0. Specifically, when the trimming head 31 swings to the edge of the polishing pad 11, the angular velocity of the trimming head 31 is 0, and when the trimming head 31 swings to the center of the polishing pad 11, the angular velocity of the trimming head 31 is 0.

[0066] Furthermore, the angular velocity w(t) of the trimming head 31 in the first swing cycle of the reciprocating swing motion satisfies:

[0067] Wherein, T1 represents the time point of 1 / 2 cycle, T2 represents the time point of one cycle, and θ represents the angle value of the dressing head 31 swinging from the edge of the polishing pad 11 to the center of the circle.

[0068] See also Figure 4 As shown, in some embodiments, when the first polishing head 21 moves from the edge of the polishing pad 11 to the center of the circle, the speed of the first polishing head 21 accelerates from 0 to the positive maximum value Vmax, moves at the positive maximum value Vmax for a certain period of time, and then decelerates from the positive maximum value Vmax to 0.

[0069] During the movement of the first polishing head 21 from the center to the edge of the polishing pad 11, the speed of the first polishing head 21 is accelerated from 0 to the negative maximum value -Vmax, and after moving at the negative maximum value -Vmax for a certain period of time, it is decelerated from the negative maximum value -Vmax to 0. Specifically, when the first polishing head 21 moves to the edge of the polishing pad 11, the speed of the first polishing head 21 is 0, and when the first polishing head 21 moves to the center of the polishing pad 11, the speed of the first polishing head 21 is 0.

[0070] Furthermore, the speed v1(t) of the first polishing head 21 in the first reciprocating movement cycle satisfies:

[0071] Wherein, when the first polishing head 21 is in the initial position, the center position of the first polishing head 21 is located at the midpoint of the first preset straight line trajectory, t1 represents the time point of 1 / 4 cycle, t2 represents the time point of 1 / 2 cycle, t3 represents the time point of 3 / 4 cycle, t4 represents the time point of one cycle, and a represents the minimum distance value between the first polishing head 21 and the center of the polishing pad 11 when it is in the initial position. It should be noted that the minimum distance value between the first polishing head 21 and the center of the polishing pad 11 when it is in the initial position refers to: when the first polishing head 21 is in the initial position, the distance between the right edge of the first polishing head 21 and the center of the polishing pad 11.

[0072] See also Figure 5 As shown, in some embodiments, when the second polishing head 22 moves from the edge of the polishing pad 11 to the center of the circle, the speed of the second polishing head 22 accelerates from 0 to the negative maximum value -Vmax, moves at the negative maximum value -Vmax for a certain period of time, and then decelerates from the negative maximum value -Vmax to 0.

[0073] When the second polishing head 22 moves from the center to the edge of the polishing pad 11, the speed of the second polishing head 22 is accelerated from 0 to the positive maximum value Vmax, and after moving at the positive maximum value Vmax for a certain period of time, it is decelerated from the positive maximum value Vmax to 0. Specifically, when the second polishing head 22 moves to the edge of the polishing pad 11, the speed of the second polishing head 22 is 0, and when the second polishing head 22 moves to the center of the polishing pad 11, the speed of the second polishing head 22 is 0.

[0074] Furthermore, the speed v2(t) of the second polishing head 22 in the first reciprocating movement cycle satisfies:

[0075] Wherein, when the second polishing head 22 is in the initial position, the center position of the second polishing head 22 is located at the midpoint of the second preset straight line trajectory, t1 represents the time point of 1 / 4 cycle, t2 represents the time point of 1 / 2 cycle, t3 represents the time point of 3 / 4 cycle, t4 represents the time point of one cycle, and a represents the minimum distance value between the second polishing head 22 and the center of the polishing pad 11 when it is in the initial position. It should be noted that the minimum distance value between the second polishing head 22 and the center of the polishing pad 11 when it is in the initial position refers to: when the second polishing head 22 is in the initial position, the distance between the left edge of the second polishing head 22 and the center of the polishing pad 11.

[0076] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A polishing device, characterized in that: include: A polishing table (10), wherein a polishing pad (11) is arranged on the polishing table (10); A polishing assembly (20) comprises a polishing head and a polishing drive, wherein the polishing head is used to absorb and fix the wafer, and the polishing drive is connected to the polishing head to drive the polishing head to drive the wafer to move along the surface of the polishing pad (11); and A dresser (30) comprising a dresser head (31) and a dresser drive, wherein the dresser drive is drivably connected to the dresser head (31) so as to drive the dresser head (31) to move along the surface of the polishing pad (11); Wherein, when the polishing head and the dressing head (31) respectively move along the surface of the polishing pad (11), the following condition is satisfied: the distance between the center position of the polishing head and the center position of the dressing head (31) is greater than the sum of the radius of the polishing head and the radius of the dressing head (31).

2. The polishing device according to claim 1, characterized in that: The polishing head comprises a first polishing head (21) and a second polishing head (22); the first polishing head (21) and the second polishing head (22), driven by the polishing drive, move synchronously back and forth along a first preset linear trajectory and a second preset linear trajectory respectively; the first preset linear trajectory and the second preset linear trajectory both extend from the center of the polishing pad (11) to the edge, and the first preset linear trajectory and the second preset linear trajectory are collinear.

3. The polishing device according to claim 2, characterized in that: Driven by the dressing drive member, the dressing head (31) swings back and forth around a fulcrum (O) between the center and the edge of the polishing pad (11).

4. The polishing device according to claim 3, characterized in that: When the first polishing head (21) and the dressing head (31) move respectively along the surface of the polishing pad (11), the following conditions are satisfied: Wherein, R represents the distance between the fulcrum (O) and the center position of the dressing head (31), t represents time, w(t) represents the angular velocity of the dressing head (31) swinging around the fulcrum (O), v1(t) represents the velocity of the first polishing head (21), and x head1 represents the X-axis coordinate of the center position of the first polishing head (21) at the initial time in a coordinate system with the fulcrum (O) as the origin, the X-axis being parallel to the first preset linear trajectory, and the Y-axis being perpendicular to the first preset linear trajectory, y head1 represents the Y-axis coordinate of the center position of the first polishing head (21) at the initial time in a coordinate system with the fulcrum (O) as the origin, the X-axis being parallel to the first preset straight line trajectory, and the Y-axis being perpendicular to the first preset straight line trajectory, θ1 represents the angle between the X-axis and the line connecting the center position of the dressing head (31) and the fulcrum (O) when the dressing head (31) moves to the center of the polishing pad (11), R pc represents the radius of the trimming head (31), R head1 represents the radius of the first polishing head (21).

5. The polishing device according to claim 3, characterized in that: When the second polishing head (22) and the dressing head (31) move along the surface of the polishing pad (11), the following conditions are satisfied: Wherein, R represents the distance between the fulcrum (O) and the center position of the dressing head (31), t represents time, w(t) represents the angular velocity of the dressing head (31) swinging around the fulcrum (O), v2(t) represents the velocity of the second polishing head (22), and x head2 represents the X-axis coordinate of the center position of the second polishing head (22) at the initial time in a coordinate system with the fulcrum (O) as the origin, the X-axis being parallel to the second preset linear trajectory, and the Y-axis being perpendicular to the second preset linear trajectory, y head2 represents the Y-axis coordinate of the center position of the second polishing head (22) at the initial time in a coordinate system with the fulcrum (O) as the origin, the X-axis being parallel to the second preset linear trajectory, and the Y-axis being perpendicular to the second preset linear trajectory, θ1 represents the angle between the X-axis and the line connecting the center position of the dressing head (31) and the fulcrum (O) when the dressing head (31) moves to the center of the polishing pad (11), R pc represents the radius of the trimming head (31), R head2 represents the radius of the second polishing head (22).

6. The polishing device according to claim 4 or 5, characterized in that: During the swinging process of the trimming head (31) from the edge of the polishing pad (11) to the center of the circle, the angular velocity of the trimming head (31) is accelerated from 0 to a positive maximum value Wmax, and then decelerated from the positive maximum value Wmax to 0; During the swinging process of the trimming head (31) from the center to the edge of the polishing pad (11), the angular velocity of the trimming head (31) is accelerated from 0 to a negative maximum value -Wmax, and then decelerated from the negative maximum value -Wmax to 0.

7. The polishing device according to claim 6, characterized in that: The angular velocity of the trimming head (31) in the first swing cycle of the reciprocating swing motion satisfies: Wherein, T1 represents the time point of 1 / 2 cycle, T2 represents the time point of one cycle, and θ represents the angle value of the trimming head (31) swinging from the edge of the polishing pad (11) to the center of the circle.

8. The polishing device according to claim 4, characterized in that: In the process of the first polishing head (21) moving from the edge of the polishing pad (11) to the center of the circle, the speed of the first polishing head (21) is accelerated from 0 to a positive maximum value Vmax, and then decelerated from the positive maximum value Vmax to 0; During the movement of the first polishing head (21) from the center to the edge of the polishing pad (11), the speed of the first polishing head (21) is accelerated from 0 to a negative maximum value -Vmax, and then decelerated from the negative maximum value -Vmax to 0.

9. The polishing device according to claim 8, characterized in that: The speed of the first polishing head (21) in the first reciprocating movement cycle satisfies: Wherein, when the first polishing head (21) is at the initial position, the center position of the first polishing head (21) is located at the midpoint of the first preset straight line trajectory, t1 represents the time point of 1 / 4 cycle, t2 represents the time point of 1 / 2 cycle, t3 represents the time point of 3 / 4 cycle, t4 represents the time point of one cycle, and a represents the minimum distance value between the first polishing head (21) and the center of the polishing pad (11) when the first polishing head (21) is at the initial position.

10. The polishing device according to claim 5, characterized in that: In the process of the second polishing head (22) moving from the edge of the polishing pad (11) to the center of the circle, the speed of the second polishing head (22) is accelerated from 0 to a negative maximum value -Vmax, and then decelerated from the negative maximum value -Vmax to 0; During the movement of the second polishing head (22) from the center to the edge of the polishing pad (11), the angular velocity of the second polishing head (22) is accelerated from 0 to a positive maximum value Vmax, and then decelerated from the positive maximum value Vmax to 0.

11. The polishing device according to claim 10, characterized in that: The speed of the second polishing head (22) in the first movement cycle of the reciprocating movement satisfies: Wherein, when the second polishing head (22) is at the initial position, the center point of the second polishing head (22) is located at the midpoint of the second preset straight line trajectory, t1 represents the time point of 1 / 4 cycle, t2 represents the time point of 1 / 2 cycle, t3 represents the time point of 3 / 4 cycle, t4 represents the time point of one cycle, and a represents the minimum distance value between the second polishing head (22) and the center of the polishing pad (11) when the second polishing head (22) is at the initial position.

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