Chemical mechanical polishing synergic control method for millimeter-scale silicon ball ultra-smooth surface

Abstract

The application discloses a kind of millimeter silicon ball ultra-smooth surface chemical mechanical polishing collaborative control methods, it is related to collaborative control technical field, including: short-range development type chemical mechanical polishing is executed to the silicon ball to be polished, to collect the full surface three-dimensional topography data of the silicon ball to be polished;According to full surface three-dimensional topography data generation short arc object;According to the extension direction of short arc object corresponding short arc, the short arc object with same extension tendency is classified into the same short arc group;According to the short arc object in the same short arc group, spherical path order and vacancy arc segment, generate mother arc system collection;Based on the executable action set of chemical mechanical polishing device and mother arc system collection, construct initial particle group;Initial particle group is iteratively updated to obtain target borrowing continuation writing sequence;The application improves the processing stability of millimeter silicon ball ultra-smooth surface.

Description

Technical Field

[0001] This invention relates to the field of collaborative control technology, and in particular to a collaborative control method for chemical mechanical polishing of millimeter-scale ultra-smooth silicon spheres. Background Technology

[0002] Millimeter-scale silicon balls are widely used in high-precision bearings, inertial devices, precision optics, semiconductor equipment, and high-end metrology. Their surface quality directly affects the fitting accuracy, tribological wear performance, and service stability of components. To obtain nanoscale surface roughness and high sphericity, chemical mechanical polishing is usually used to complete the final ultra-precision machining. This process uses chemical reactions to soften the surface material of the silicon ball, and then removes the material through the relative movement between the polishing pad, abrasive grains, and silicon ball.

[0003] In actual processing, the surface of the polishing pad is covered with a large number of micropores. Under long-term pressure and wear, the edges of the micropores are prone to forming local micro-protrusions. When the silicon ball to be polished is in continuous contact with the polishing pad and relative motion occurs, the local micro-protrusions will periodically sweep across the surface of the silicon ball, forming intermittent short arc-shaped polishing marks only in the local contact area. There are spherical interval areas between two adjacent short arcs that are not covered by the local micro-protrusions. This causes multiple discontinuous short arcs to form spherical action trajectories with a continuous trend but not continuous along the same spherical extension direction. As the polishing process continues, these spherical action trajectories will gradually accumulate and have a continuous impact on the formation process of the ultra-smooth surface of the silicon ball.

[0004] Existing chemical mechanical polishing methods mainly adjust the processing based on macroscopic process parameters such as polishing pressure, rotation speed, polishing time, and material removal, or make feedback corrections based on the overall surface morphology results. However, they pay less attention to the spherical continuity relationship between the discontinuous short arcs formed by the local micro-protrusions at the edge of the polishing pad micropores on the silicon sphere surface. Therefore, when the local micro-protrusions sweep across the silicon sphere surface multiple times, the empty spherical areas formed between adjacent discontinuous short arcs cannot be effectively identified and compensated for. This causes the subsequent motion trajectory to easily deviate from the existing spherical action trajectory, resulting in repeated polishing in non-target areas. Meanwhile, the original empty spherical areas are still not fully covered, leading to uneven distribution of local material removal. Ultimately, this affects the uniformity and processing stability of the ultra-smooth surface of the millimeter-scale silicon sphere. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies that affect the uniformity and processing stability of ultra-smooth surfaces of millimeter-sized silicon spheres, and to propose a chemical mechanical polishing synergistic control method for ultra-smooth surfaces of millimeter-sized silicon spheres.

[0006] To address the problems existing in the prior art, the present invention adopts the following technical solution: A method for synergistic control of chemical mechanical polishing on ultra-smooth surfaces of millimeter-scale silicon spheres includes: S1. Perform short-range developing chemical mechanical polishing on the silicon sphere to be polished to collect full-surface three-dimensional morphology data of the silicon sphere; generate a short-arc object based on the full-surface three-dimensional morphology data; S2. Based on the extension direction of the short arc corresponding to the short arc object, group short arc objects with the same extension trend into the same short arc group; generate a set of parent arc systems based on the short arc objects, spherical path order and missing arc segments within the same short arc group. S3. Based on the set of executable actions and the set of parent arc systems of the chemical mechanical polishing device, construct an initial particle swarm; iteratively update the initial particle swarm to obtain the target borrowing continuation sequence; S4. Based on the target borrowing continuation sequence, perform coordinated motion control on the silicon ball to be polished and the polishing pad to generate a pose motion combination result; S5. Based on the local micro-convex structure of the polishing pad, define the discontinuous arc mark at the hole edge; based on the combined position and motion results, obtain the collaborative control sequence code corresponding to the discontinuous arc mark at the hole edge, and perform collaborative control on the ball carrier mechanism, the silicon ball to be polished, and the polishing pad.

[0007] Preferably, the three-dimensional morphology data of the entire surface of the silicon sphere to be polished is collected, including: Identify the local micro-protrusion structure at the edge of the micropores in the polishing pad; The silicon ball to be polished is clamped and the contact between the silicon ball and the polishing pad is controlled. Short-range developing chemical mechanical polishing is performed on the silicon ball to be polished so that the local micro-protrusion structure forms discontinuous short arcs on the surface of the silicon ball to be polished. After short-range developing chemical mechanical polishing, the full-surface three-dimensional morphology data of the silicon sphere to be polished are collected.

[0008] Preferably, generating a short arc object includes: Extract the spherical position data, arc direction data, and sphere center angle data of discontinuous short arcs from the full-surface three-dimensional topography data; Obtain the radius of the silicon sphere to be polished; Calculate the arc length of the discontinuous short arc based on the radius of the silicon sphere and the central angle of the discontinuous short arc. Associate the spherical position data, arc direction data, and arc length data into a short arc object.

[0009] Preferably, short arc objects with the same extension trend are grouped into the same short arc group, including: Gather all short arc objects into a short arc set; Based on the spherical position data of the short arc object, determine the starting point and ending point of the short arc object in the spherical coordinates of the silicon sphere to be polished; Based on the arc direction data of the short arc object, determine the extension direction of the short arc corresponding to the short arc object; Based on the starting point, ending point, and extension direction of the short arc, short arc objects with the same extension trend in the short arc set are grouped into the same short arc group.

[0010] Preferably, generating the parent arc system set includes: Based on the starting and ending points of the short arcs of each short arc object in the same short arc group, the spherical path order is arranged for each short arc object in the same short arc group to obtain the spherical path order. Based on the short arc endpoint and short arc start point of two adjacent short arc objects in the same short arc group, generate the missing arc segment between two adjacent short arc objects; Associate the short arc objects, spherical path sequence, and missing arc segments within the same short arc group as a parent arc system; All parent arc systems are combined into a parent arc system set.

[0011] Preferably, constructing the initial particle swarm includes: Obtain the set of executable actions of the chemical mechanical polishing device; wherein, the set of executable actions includes ball attitude switching action, silicon ball rotation direction alternation action and ball relative motion direction rotation action; Based on the set of executable actions, construct candidate borrowing continuation sequences; The candidate borrowed continuation sequence is used as a particle in the particle swarm algorithm; The initial position of the particle is determined by the execution order of each action in the candidate borrow continuation sequence; The initial velocity of the particle is determined by the execution order of each action in the empty arc segment in the parent arc system set and the candidate borrowed continuation sequence. An initial particle swarm is constructed based on the initial velocity and initial position of the particles.

[0012] Preferably, obtaining the target borrow continuation sequence includes: Based on the empty arc segments in the mother arc system set, obtain the empty arc segment coverage length corresponding to the candidate borrow continuation sequence; Based on the spherical path order in the parent arc system set, obtain the length of the side arc segment corresponding to the candidate borrowed continuation sequence; The evaluation value of the candidate borrowed continuation sequence is calculated based on the coverage length of the missing arc segment and the length of the side arc segment. Based on the evaluation metrics, determine the individual optimal position and the global optimal position; The initial particle swarm is iteratively updated using the individual optimal position and the global optimal position to obtain the particle swarm after the iteration. Based on the particle swarm after the iteration, the target borrowing continuation sequence is obtained.

[0013] Preferably, generating the pose motion combination result includes: According to the execution order of the ball attitude switching action in the target borrow continuation sequence, control the contact attitude of the silicon ball to be polished relative to the polishing pad. According to the execution order of the alternating action of the silicon sphere's rotation direction in the target borrow continuation sequence, control the silicon sphere to be polished to switch its rotation direction; According to the execution order of the ball-dribble relative motion direction rotation action in the target borrowing continuation sequence, control the switching of relative motion direction between the silicon ball to be polished and the polishing pad; The results of switching contact posture, switching rotation direction, and switching relative motion direction are correlated into a pose motion combination result.

[0014] Preferably, the ball carrier mechanism, the silicon ball to be polished, and the polishing pad are controlled in a coordinated manner, including: Extract the execution order of ball posture switching actions, the execution order of alternating actions of silicon ball rotation direction, and the execution order of ball dribbling relative motion direction rotation actions from the combined posture motion results; The discontinuous short arcs formed by local micro-protrusions on the surface of the silicon sphere to be polished are defined as discontinuous arc marks at the hole edge. The execution order of the ball attitude switching action, the execution order of the silicon ball rotation direction alternation action, and the execution order of the ball relative motion direction rotation action are sequentially encoded to obtain the collaborative control sequence code corresponding to the discontinuous arc mark on the hole edge. Based on the collaborative control sequence code, the ball carrier mechanism, the silicon ball to be polished, and the polishing pad are controlled collaboratively.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention identifies discontinuous short arcs on the surface of a silicon sphere to be polished and constructs a set of parent arc systems. It associates discretely distributed arc marks with continuous spherical paths, accurately characterizes the empty spherical regions between adjacent discontinuous short arcs, provides a basis for the generation of subsequent borrowed continuation sequences, and improves the accuracy of identifying empty regions.

[0016] 2. This invention calculates the evaluation value of candidate borrowed continuation sequences based on the coverage length of the missing arc segment and the length of the bypass arc segment, and uses the particle swarm optimization algorithm for iterative optimization, so that the target borrowed continuation sequence can preferentially cover the missing spherical area, reduce the invalid polishing that deviates from the existing spherical path, and improve the uniformity of material removal.

[0017] 3. This invention generates a cooperative control sequence code based on the target borrow continuation sequence, and performs cooperative control on the ball's attitude, rotation direction, and relative motion direction of the ball, guiding the local micro-convex structure to complete the continuation along the corresponding spherical path of the parent arc system, reducing repeated polishing, and improving the processing stability and surface quality of the millimeter-level silicon ball's ultra-smooth surface. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart illustrating a chemical mechanical polishing synergistic control method for an ultra-smooth surface of millimeter-scale silicon spheres, provided as an embodiment of the present invention. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] This embodiment provides a method for the coordinated control of chemical mechanical polishing on the ultra-smooth surface of millimeter-scale silicon spheres. See [link to relevant documentation]. Figure 1 Specifically, including: S1. Perform short-range developing chemical mechanical polishing on the silicon sphere to be polished to collect full-surface three-dimensional morphology data of the silicon sphere; generate a short-arc object based on the full-surface three-dimensional morphology data; In an embodiment of the present invention, the three-dimensional morphology data of the entire surface of the silicon sphere to be polished is collected, including: Identify the local micro-protrusion structure at the edge of the micropores in the polishing pad; Local micro-protrusion structure refers to the micro-solid structure formed by the local height protrusion of the edge region of the micropore of the polishing pad relative to the surface of the surrounding polishing pad. This local height protrusion can preferentially contact the surface of the silicon ball to be polished during the polishing process and form a stable local contact unit. A polishing pad for short-range developing chemical mechanical polishing is installed on the polishing pad support of the polishing device, with the working surface of the polishing pad facing the clamping direction of the silicon ball to be polished. The working surface of the polishing pad is scanned and collected using a surface morphology detection device to obtain surface height data. Based on the surface height data, the micropore region in the working surface of the polishing pad is identified. The boundary region of the micropore region is taken as the micropore edge region. The solid part protruding outward relative to the adjacent working surface of the polishing pad in the micropore edge region is identified as a local micro-protrusion structure, and the regional position of the local micro-protrusion structure on the working surface of the polishing pad is recorded.

[0021] The silicon ball to be polished is clamped and the contact between the silicon ball and the polishing pad is controlled. Short-range developing chemical mechanical polishing is performed on the silicon ball to be polished so that the local micro-protrusion structure forms discontinuous short arcs on the surface of the silicon ball to be polished. Short-range developing chemical mechanical polishing refers to the process of shortening the polishing duration while maintaining the same polishing pad, polishing slurry, contact load, and relative motion as formal chemical mechanical polishing. This allows the local micro-protrusions at the edge of the micropores of the polishing pad to leave initial action marks on the surface of the silicon ball to be polished, reflecting the actual contact state, without aiming to complete the final surface polishing. Discontinuous short arcs refer to the multiple separate arc-shaped action marks formed by the local micro-protrusions contacting the surface of the silicon ball multiple times during the rolling, rotation, and relative sliding of the silicon ball to be polished. These arc-shaped action marks are distributed along similar arc directions and are separated from each other. There are intervals between each arc-shaped action mark where no continuous contact occurs. The silicon ball to be polished is placed into the ball receiving part of the ball carrier mechanism, allowing the silicon ball to roll within the ball receiving part. The ball carrier mechanism is then moved above the working surface of the polishing pad, so that the spherical surface of the silicon ball to be polished contacts the working surface of the polishing pad. Chemical mechanical polishing slurry is supplied to the contact area between the silicon ball to be polished and the polishing pad, driving the polishing pad and the ball carrier mechanism to generate relative motion. This causes the local micro-protrusion structure to enter the contact area along with the working surface of the polishing pad. Short-range developing chemical mechanical polishing is then performed on the silicon ball to be polished, causing the local micro-protrusion structure to form discontinuous short arcs on the surface of the silicon ball to be polished.

[0022] After short-range developing chemical mechanical polishing, the full-surface three-dimensional morphology data of the silicon sphere to be polished are collected.

[0023] Full-surface three-dimensional topography data refers to spatial topography information covering the entire surface range of the silicon sphere to be polished. This spatial topography information includes at least the spatial coordinates and surface height distribution corresponding to each position on the sphere, and is used to characterize the micro-geometry of the entire surface of the silicon sphere to be polished.

[0024] After short-range developing chemical mechanical polishing is completed, the relative movement between the polishing pad and the ball carrier mechanism is stopped, the supply of chemical mechanical polishing slurry to the contact area is stopped, the silicon ball to be polished is removed from the ball carrier mechanism, the free slurry and residual particles on the surface of the silicon ball to be polished are removed, the cleaned silicon ball to be polished is placed on the ball support of the spherical morphology acquisition device, the ball support is controlled to drive the silicon ball to be polished to rotate, so that the spherical morphology acquisition device covers the entire spherical surface of the silicon ball to be polished, and the full surface three-dimensional morphology data of the silicon ball to be polished are collected.

[0025] In an embodiment of the present invention, generating a short arc object includes: Extract the spherical position data, arc direction data, and sphere center angle data of discontinuous short arcs from the full-surface three-dimensional topography data; Spherical position data refers to the spatial distribution information of discontinuous short arcs on the surface of the silicon sphere to be polished. This spatial distribution information is used to determine the specific area of ​​the discontinuous short arcs on the surface of the silicon sphere and the relative positional relationship between different discontinuous short arcs. Arc direction data refers to the direction information of the discontinuous short arcs extending along the surface of the silicon sphere to be polished. This information is used to characterize the extension direction of the discontinuous short arcs on the sphere and the directional relationship between different discontinuous short arcs. Center angle data refers to the angle information formed by the lines connecting the center of the silicon sphere to be polished to the corresponding spherical points at both ends of the discontinuous short arcs. This information is used to characterize the angular size of the spherical range corresponding to the discontinuous short arcs. Specifically, the full-surface 3D topographic data of the silicon sphere to be polished is imported into a 3D topographic processing unit. All sampling points are mapped onto the surface of the silicon sphere according to spatial coordinates. All sampling points are connected to form a continuous spherical mesh. The spherical mesh is unfolded row by row along the latitude and longitude directions of the sphere. The unfolded spherical mesh is continuously traversed, and the height changes between adjacent sampling points are compared. Sampling points with continuously decreasing heights and maintaining an arc-shaped extension relationship are connected point by point to form candidate arc segments. Sampling points on both sides of the candidate arc segment that no longer satisfy the continuous extension relationship are used as the boundary points of the candidate arc segment. All sampling points between the boundary points are retained as the same discontinuous short arc. All sampling points within the area covered by the discontinuous short arc are then processed. The points are reprojected onto the surface of the silicon sphere to be polished, and a spherical coverage area is formed by enclosing all the projected points. The center position of the spherical coverage area is recorded as the spherical position data. All the projected points within the spherical coverage area are reassembled in the connection order to form a spherical arc. The starting and ending points of the spherical arc are connected to form a chord. A perpendicular tangential direction to the chord is established in the middle of the spherical arc. The extension direction of the spherical arc along the tangential direction is recorded as the arc direction data. Then, the center of the silicon sphere to be polished is connected to the starting and ending points of the spherical arc to form two lines connecting the centers of the sphere. The included angle of the two lines connecting the centers of the sphere is measured, and the measured included angle is recorded as the spherical central angle data corresponding to the discontinuous short arc.

[0026] Associate the spherical position data, arc direction data, and arc length data into a short arc object.

[0027] A short arc object refers to a data object created on the basis of a single discontinuous short arc. This data object includes the spherical position data, arc direction data, and arc length data of the corresponding discontinuous short arc, which is used to completely describe the spatial state of a single discontinuous short arc on the surface of the silicon sphere to be polished. The extracted spherical position data, arc direction data, and central angle data are grouped according to the same source of discontinuous short arcs. The spherical position data corresponding to the same discontinuous short arc is used as the position field of the short arc object, the arc direction data corresponding to the same discontinuous short arc is used as the direction field of the short arc object, and the central angle data corresponding to the same discontinuous short arc is used as the angle field of the short arc object. The position field, direction field, and angle field are written into the same data record unit, and the data record unit is named the short arc object.

[0028] Obtain the radius of the silicon sphere to be polished; The silicon sphere to be polished is placed on the sphere support of the sphere diameter measuring device, keeping the silicon sphere rotatable. The sphere support is driven to rotate the silicon sphere, and diameter data between multiple spherical positions of the silicon sphere are collected. The diameter of the silicon sphere is obtained by averaging the multiple diameter data. The radius of the silicon sphere is obtained by dividing the diameter of the silicon sphere by two.

[0029] Calculate the arc length of the discontinuous short arc based on the radius of the silicon sphere and the central angle of the discontinuous short arc. Arc length data refers to the curve length information formed by the actual extension of the discontinuous short arc along the surface of the silicon sphere to be polished, which is used to characterize the actual range of action of the discontinuous short arc on the sphere. Retrieve the silicon sphere radius and the central angle data of the short arc object from the silicon sphere to be polished. Convert the central angle data into radian angle data. Multiply the silicon sphere radius and the radian angle data to obtain the arc length data of the discontinuous short arc.

[0030] It should be noted that the outer surface of the silicon sphere to be polished is spherical, and the discontinuous short arc is formed on the spherical surface. Its starting and ending points are both located on the same spherical surface. When connecting the center of the silicon sphere to the starting and ending points of the discontinuous short arc, both connecting lines are radii of the sphere. The angle formed between the two radii is the central angle corresponding to the discontinuous short arc. According to spherical geometry, the actual length of any arc on a sphere is determined only by the sphere's radius and the corresponding central angle. When the central angle is expressed in radians, the length of the spherical arc is equal to half the length of the sphere. The product of the radius and the central angle is used to calculate the arc length of the discontinuous short arc by using the radius of the silicon sphere to be polished and the central angle corresponding to the discontinuous short arc. This result is the arc length data formed by the actual extension of the discontinuous short arc along the surface of the silicon sphere to be polished. This arc length data can truly reflect the actual length of the local micro-convex structure on the surface of the silicon sphere to be polished, and will not be affected by the projection direction of the discontinuous short arc in three-dimensional space or the change of the spherical position. Therefore, the calculation of the arc length data of the discontinuous short arc by using the radius of the silicon sphere and the central angle conforms to the geometric relationship of the spherical surface and the calculation law of the spherical arc length.

[0031] S2. Based on the extension direction of the short arc corresponding to the short arc object, group short arc objects with the same extension trend into the same short arc group; generate a set of parent arc systems based on the short arc objects, spherical path order and missing arc segments within the same short arc group. In embodiments of the present invention, grouping short arc objects with the same extension trend into the same short arc group includes: Gather all short arc objects into a short arc set; A short arc set refers to a data set formed by a collection of multiple short arc objects, each of which corresponds to a discontinuous short arc on the surface of the silicon sphere to be polished. Specifically, each short arc object generated in the previous steps is loaded into the same data storage area, the spherical position data, arc direction data, and arc length data in each short arc object are kept as the same data record, all data records are written to the same collection file in the order of generation, and the collection file is marked as a short arc collection.

[0032] Based on the spherical position data of the short arc object, determine the starting point and ending point of the short arc object in the spherical coordinates of the silicon sphere to be polished; The starting point of a short arc refers to the position at which the short arc object begins to extend along the arc direction on the surface of the silicon sphere to be polished, and is used to indicate the starting boundary of a single discontinuous short arc; the ending point of a short arc refers to the position at which the short arc object ends to extend along the arc direction on the surface of the silicon sphere to be polished, and is used to indicate the ending boundary of a single discontinuous short arc. The spherical position data in the short arc object is converted into the spherical coordinates of the silicon sphere to be polished. All spherical sampling points covered by the spherical position data are arranged according to the arc direction data of the short arc object. The spherical sampling point located at the beginning of the extension direction after arrangement is recorded as the starting point of the short arc, and the spherical sampling point located at the end of the extension direction after arrangement is recorded as the ending point of the short arc.

[0033] Based on the arc direction data of the short arc object, determine the extension direction of the short arc corresponding to the short arc object; The short arc extension direction refers to the direction in which the short arc object extends from the starting point of the short arc to the ending point of the short arc and unfolds along the surface of the silicon sphere to be polished. It is used to indicate the direction of the discontinuous short arc on the sphere. The arc direction data in the short arc object is imported into the spherical coordinate system. The direction line corresponding to the arc direction data is projected onto the spherical tangent plane of the silicon sphere to be polished. The projected direction line is matched with the spherical connection direction from the start point to the end point of the short arc. The direction from the start point of the short arc to the end point of the short arc and extending along the spherical connection direction is recorded as the short arc extension direction. The short arc extension direction is written into the corresponding short arc object.

[0034] Based on the starting point, ending point, and extension direction of the short arc, short arc objects with the same extension trend in the short arc set are grouped into the same short arc group.

[0035] A short arc group refers to a data group formed by aggregating multiple short arc objects with the same extension trend from a short arc set. It is used to indicate that multiple short arc objects belong to the same arc direction distribution relationship on the surface of the silicon sphere to be polished.

[0036] Each short arc object in the short arc set is brought into the grouping process. The starting point, ending point, and extension direction of the short arc of each short arc object are used as the grouping criteria. Short arc objects with the same extension direction and whose starting point and ending point are distributed along the same spherical extension route are grouped into the same short arc group. The short arc groups after the grouping process is completed are saved as a short arc group set.

[0037] In an embodiment of the present invention, generating a set of parent arc systems includes: Based on the starting and ending points of the short arcs of each short arc object in the same short arc group, the spherical path order is arranged for each short arc object in the same short arc group to obtain the spherical path order. The spherical path sequence refers to the order in which the short arc objects within the same short arc group are arranged along the natural extension direction of the spherical surface of the silicon sphere to be polished, and is used to represent the continuous distribution relationship of multiple short arc objects on the spherical surface; Map the starting and ending points of each short arc object within the same short arc group to the spherical coordinates of the silicon sphere to be polished. Connect the starting and ending points of each short arc object to form the corresponding spherical short arc. Sequentially splice all the spherical short arcs within the same short arc group along the short arc extension direction. Use the ending point of one spherical short arc and the starting point of another spherical short arc as adjacent connection ends. Arrange the spherical short arcs that can be continuously connected along the same spherical extension path in adjacent positions. Record the order of the short arc objects on the surface of the silicon sphere to be polished as the spherical path sequence.

[0038] Based on the short arc endpoint and short arc start point of two adjacent short arc objects in the same short arc group, generate the missing arc segment between two adjacent short arc objects; A gap arc segment refers to a spherical arc region in which no discontinuous short arc is formed between two adjacent short arc objects within the same short arc group. This spherical arc region is located between the end point of the short arc of the previous short arc object and the beginning point of the short arc of the next short arc object. It is used to represent the interval region in which the local micro-convex structure does not play an actual role in the continuous extension of the spherical surface. In the spherical path sequence of the same short arc group, select two adjacent short arc objects in sequence. Take the end point of the short arc of the previous short arc object as the starting point of the missing arc segment, and take the starting point of the short arc of the next short arc object as the ending point of the missing arc segment. Connect the starting point and ending point of the missing arc segment in the spherical coordinates of the silicon sphere to be polished. Take the spherical arc obtained by the connection as the missing arc segment between two adjacent short arc objects, and write the missing arc segment into the data record of the corresponding short arc group.

[0039] Associate the short arc objects, spherical path sequence, and missing arc segments within the same short arc group as a parent arc system; The mother arc system refers to the complete spherical arc data set formed by associating all short arc objects in the same short arc group, the corresponding spherical path sequence, and the empty arc segments between adjacent short arc objects. It is used to represent a continuous spherical action trajectory corresponding to multiple discontinuous short arcs. All short arc objects within the same short arc group are used as the short arc data of the parent arc system, the spherical path sequence is used as the arrangement data of the parent arc system, and all empty arc segments between two adjacent short arc objects are used as the interval data of the parent arc system. The short arc data, arrangement data, and interval data are written into the same parent arc system data record, so that the same parent arc system data record can simultaneously represent the spherical position relationship, arrangement relationship, and interval relationship of each discontinuous short arc within the same short arc group.

[0040] All parent arc systems are combined into a parent arc system set.

[0041] The set of parent arc systems refers to the data set formed by the collection of all parent arc systems, which is used to store the spatial distribution relationship between all continuous spherical action trajectories on the surface of the silicon sphere to be polished.

[0042] Each parent arc system data record is loaded into the same set storage area. The corresponding short arc data, arrangement data, and interval data are retained for each parent arc system data record. All parent arc system data records are written into the same data set in the order of generation. This data set is named the parent arc system set.

[0043] For example, the short arc set includes a first short arc object, a second short arc object, a third short arc object, and a fourth short arc object. The starting point of the short arc of the first short arc object is at 12°N, 20°E on spherical coordinates, and the ending point is at 12°N, 35°E on spherical coordinates. The starting point of the short arc of the second short arc object is at 12°N, 42°E on spherical coordinates, and the ending point is at 12°N, 55°E on spherical coordinates. The starting point of the short arc of the third short arc object is at 12°N, 63°E on spherical coordinates, and the ending point is at 12°N, 78°E on spherical coordinates. The starting point of the short arc of the fourth short arc object is at 18°S, 110°E on spherical coordinates, and the ending point is at 18°S, 128°E on spherical coordinates. Based on the spherical distribution of the starting and ending points of the short arcs, the first short arc object... The second and third short arc objects are arranged in spherical path order from 20°E to 78°E. The spherical arc segment between the short arc endpoint of the first short arc object at 35°E and the short arc starting point of the second short arc object at 42°E is generated as the first missing arc segment. The spherical arc segment between the short arc endpoint of the second short arc object at 55°E and the short arc starting point of the third short arc object at 63°E is generated as the second missing arc segment. The first short arc object, the second short arc object, the third short arc object, the spherical path order from 20°E to 78°E, the first missing arc segment, and the second missing arc segment are associated as the first parent arc system. The fourth short arc object and its corresponding spherical path order from 18°S to 110°E to 128°E are associated as the second parent arc system. The first parent arc system and the second parent arc system form a parent arc system set.

[0044] Based on the extension direction of the short arc objects, short arc objects with the same extension trend are grouped into the same short arc group. A set of parent arc systems is generated based on the short arc objects, spherical path sequence, and missing arc segments within the same short arc group. This establishes a continuous spherical relationship between the originally discrete and discontinuous short arcs. At the same time, the uncovered spherical areas between adjacent discontinuous short arcs are converted into missing arc segments for unified representation. This avoids deviation from the existing spherical action trajectory in the subsequent polishing process, provides a continuous spherical path basis for the subsequent construction of borrowed continuation sequences, improves the coverage of missing spherical areas, and improves the uniformity of local material removal distribution.

[0045] S3. Based on the set of executable actions and the set of parent arc systems of the chemical mechanical polishing device, construct an initial particle swarm; iteratively update the initial particle swarm to obtain the target borrowing continuation sequence; In an embodiment of the present invention, constructing an initial particle swarm includes: Obtain the set of executable actions of the chemical mechanical polishing device; wherein, the set of executable actions includes ball attitude switching action, silicon ball rotation direction alternation action and ball relative motion direction rotation action; The set of executable actions refers to the data set of motion actions that the chemical mechanical polishing device can directly execute. This data set is used to limit the types of actions that can be called by the candidate borrow continuation sequence. The ball-carrying posture switching action refers to the motion action of the ball-carrying mechanism to change the contact posture of the silicon ball to be polished relative to the polishing pad, which is used to change the contact area between the surface of the silicon ball to be polished and the polishing pad. The silicon ball rotation direction alternation action refers to the motion action of the silicon ball to be polished changing the rotation direction around its own center, which is used to change the direction of the surface of the silicon ball to be polished through the contact area of ​​the polishing pad. The ball relative motion direction rotation action refers to the motion action of switching the relative sliding direction between the polishing pad and the silicon ball to be polished, which is used to change the movement direction of the local micro-protrusion structure relative to the surface of the silicon ball to be polished. The motion actions that can be performed by the ball carrier mechanism, the silicon ball rotation drive unit, and the polishing pad drive unit in the chemical mechanical polishing apparatus are retrieved. The action of changing the contact posture of the silicon ball to be polished that can be performed by the ball carrier mechanism is recorded as the ball carrier posture switching action. The action of changing the rotation direction of the silicon ball to be polished that can be performed by the silicon ball rotation drive unit is recorded as the silicon ball rotation direction alternation action. The action of changing the relative motion direction between the polishing pad drive unit and the ball carrier mechanism is recorded as the ball-distribution relative motion direction rotation action. The ball carrier posture switching action, the silicon ball rotation direction alternation action, and the ball-distribution relative motion direction rotation action are combined into an executable action set.

[0046] Based on the set of executable actions, construct candidate borrowing continuation sequences; Candidate borrowing continuation sequence refers to a candidate control sequence formed by combining ball posture switching action, silicon ball rotation direction alternating action, and ball dribbling relative motion direction rotation action in the execution order; Extract the ball-carrying posture switching action, the silicon ball rotation direction alternation action, and the ball-dribble relative motion direction rotation action from the set of executable actions. Arrange the three types of actions according to the action categories in the set of executable actions. Then, match the three types of actions with the spherical path sequence and empty arc segments in the parent arc system set, so that each empty arc segment corresponds to at least one ball-carrying posture switching action, one silicon ball rotation direction alternation action, and one ball-dribble relative motion direction rotation action. Combine the three types of actions after the matching is completed according to the order of the empty arc segments in the spherical path sequence to obtain the candidate borrow continuation sequence.

[0047] The candidate borrowed continuation sequence is used as a particle in the particle swarm algorithm; Each candidate borrowing continuation sequence is numbered and assigned a unique particle number. The ball attitude switching action, silicon ball rotation direction alternation action, and ball relative motion direction rotation action in the candidate borrowing continuation sequence are unfolded in sequence according to their execution order to form an action arrangement chain. Each action in the action arrangement chain is written into the same particle data record in the order of appearance. The arrangement number of the action in the action arrangement chain is written into the data item of the corresponding action. All action data items are stored continuously in the data record of the corresponding particle, so that each particle completely saves the execution content and execution order of all actions in the corresponding candidate borrowing continuation sequence, and each particle corresponds to only one candidate borrowing continuation sequence.

[0048] The initial position of the particle is determined by the execution order of each action in the candidate borrow continuation sequence; In particle swarm optimization, a particle refers to a candidate solution representing a set of candidate borrowing continuation sequences; the initial position refers to the execution order of the candidate borrowing continuation sequence corresponding to the particle at the beginning of the particle swarm optimization algorithm. Extract all actions from the action permutation chain sequentially from the particle data record. Write the first action in the action permutation chain into the first position of the position sequence, write the second action in the action permutation chain into the second position of the position sequence, and write the remaining actions in the action permutation chain into the corresponding positions of the position sequence in the order of the action permutation chain. This ensures that the position sequence maintains the same arrangement relationship as the action permutation chain. Save the resulting position sequence to the position data area of ​​the corresponding particle and use the position sequence as the initial position of the particle. This ensures that the particle maintains the same action execution order as the candidate borrow continuation sequence when the particle swarm algorithm starts calculation.

[0049] The initial velocity of the particle is determined by the execution order of each action in the empty arc segment in the parent arc system set and the candidate borrowed continuation sequence. The missing arc segments contained in each parent arc system set are expanded into a sequence of missing arc segments to be continued according to the spherical path order. The actions in the candidate borrowing continuation sequence are expanded into an action execution sequence according to the execution order. The first action in the action execution sequence is matched with the first missing arc segment in the sequence of missing arc segments to be continued, and the second action in the action execution sequence is matched with the second missing arc segment in the sequence of missing arc segments to be continued. The sequence of all actions and all missing arc segments is matched in the same way. The spherical coordinates of the starting end and the ending end of each missing arc segment are extracted. The coordinate difference obtained by subtracting the spherical coordinates of the starting end from the spherical coordinates of the ending end of the same missing arc segment is calculated. The coordinate difference is used as the displacement vector of the corresponding action. The difference of the arrangement number of two adjacent actions in the action execution sequence is obtained. The displacement vector is divided by the difference of the arrangement number to obtain the initial velocity value of the corresponding action. The initial velocity values ​​of all actions are written into the same velocity data record according to the arrangement order of the action execution sequence. The velocity data record is used as the initial velocity of the particle.

[0050] It should be noted that the initial velocity of a particle in the particle swarm optimization algorithm represents the magnitude of change of the particle during the first iteration. Essentially, it corresponds to the initial rate of change of the particle's current position relative to the target adjustment direction. In this implementation, each action corresponds to a missing arc segment in the parent arc system. The execution order between adjacent actions corresponds to adjacent positions in the particle's position. The coordinate difference between the start and end points of the missing arc segment reflects the spherical displacement required for the corresponding action. The difference in action execution sequence numbers reflects the number of action steps required to complete this spherical displacement. According to the fundamental kinematic principle that velocity equals displacement divided by time, when the number of action execution steps is used as a unified... When the discrete time unit is , the difference in action execution sequence number can be equivalently represented by the discrete time interval. Therefore, dividing the coordinate difference of the missing arc segment by the difference in action execution sequence number yields the change in spherical displacement within a unit number of action steps. This change can characterize the initial change velocity of the particle in the action arrangement space and can be directly used as the position update amount during the initial iteration of the particle swarm algorithm. Therefore, using the result calculated by the difference in coordinates of the missing arc segment and the difference in action execution sequence number as the initial velocity of the particle is consistent with the definition of velocity in discrete motion and can also reflect the initial change capability of the candidate borrow continuation sequence in adjusting towards filling the missing arc segment.

[0051] An initial particle swarm is constructed based on the initial velocity and initial position of the particles.

[0052] Initial velocity refers to the direction of change of the order in which particles adjust the execution of actions at the beginning of the particle swarm algorithm; initial particle swarm refers to a data set consisting of multiple particles with initial positions and initial velocities.

[0053] The initial position and initial velocity of each particle are loaded into the same particle data record. The initial position is used as the current action arrangement state of the candidate borrowing continuation sequence corresponding to the particle, and the initial velocity is used as the action adjustment direction of the candidate borrowing continuation sequence corresponding to the particle. All particles that have been written with initial position and initial velocity are gathered into the same particle set according to particle number, and the particle set is saved as the initial particle swarm.

[0054] In an embodiment of the present invention, obtaining the target borrow continuation sequence includes: Based on the empty arc segments in the mother arc system set, obtain the empty arc segment coverage length corresponding to the candidate borrow continuation sequence; The vacant arc segment coverage length refers to the arc length that the candidate borrow continuation sequence can fall within the vacant arc segment range of the parent arc system set after execution. It is used to represent the degree of coverage of the spherical interval area not occupied by short arc objects by the candidate borrow continuation sequence. The parent arc systems in the parent arc system set are loaded one by one. The empty arc segments in each parent arc system are expanded into a list of coverable empty arc segments according to the spherical path order. The ball attitude switching action, silicon ball rotation direction alternation action, and ball relative motion direction rotation action in the candidate borrowing continuation sequence are expanded into an action execution list according to the execution order. Each action in the action execution list is mapped to the corresponding empty arc segment in the list of coverable empty arc segments. The start and end ends of each mapped empty arc segment are projected onto the spherical reference of the silicon ball to be polished. The center of the silicon ball to be polished is connected to the start and end ends of the empty arc segments respectively, and the corresponding sphere center angle is measured. The radius of the silicon ball to be polished is multiplied by the corresponding sphere center angle to obtain the coverage arc length of a single empty arc segment. All coverage arc lengths corresponding to each action in the candidate borrowing continuation sequence are added together to obtain the coverage length of the empty arc segment corresponding to the candidate borrowing continuation sequence.

[0055] Based on the spherical path order in the parent arc system set, obtain the length of the side arc segment corresponding to the candidate borrowed continuation sequence; The bypass arc length refers to the arc length formed by the deviation of the candidate borrow continuation sequence from the spherical path order in the set of parent arc systems after execution, and is used to indicate the degree to which the action sequence deviates from the extension route of the existing parent arc system; the evaluation quantity refers to the amount of data used to compare the merits of different candidate borrow continuation sequences. The spherical path sequence in the parent arc system set is loaded. The re-landing trajectory formed on the surface of the silicon sphere to be polished after each action in the candidate borrowing continuation sequence is projected onto the spherical reference of the silicon sphere to be polished. The re-landing trajectory is overlapped and separated with the spherical path sequence in the parent arc system set. The re-landing trajectory within the arc range corresponding to the spherical path sequence that does not fall into the spherical path sequence is extracted as a bypass arc segment. The start and end ends of each bypass arc segment are projected onto the spherical reference of the silicon sphere to be polished. The center of the silicon sphere to be polished is connected to the start and end ends of the bypass arc segment respectively, and the corresponding central angle is measured. The radius of the silicon sphere to be polished is multiplied by the corresponding central angle to obtain the arc length of a single bypass arc segment. The arc lengths of all bypass arc segments corresponding to the candidate borrowing continuation sequence are added together to obtain the length of the bypass arc segment corresponding to the candidate borrowing continuation sequence.

[0056] The evaluation value of the candidate borrowed continuation sequence is calculated based on the coverage length of the missing arc segment and the length of the side arc segment. The length of the missing arc segment corresponding to the candidate borrowing continuation sequence is used as positive evaluation data, and the length of the lateral arc segment corresponding to the candidate borrowing continuation sequence is used as negative evaluation data. The evaluation value of the candidate borrowing continuation sequence is obtained by subtracting the length of the lateral arc segment from the length of the missing arc segment. The evaluation value is written into the data record of the corresponding candidate borrowing continuation sequence so that each group of candidate borrowing continuation sequences has a corresponding evaluation value.

[0057] It should be noted that the missing arc segments in the parent arc system set correspond to the spherical regions that the local micro-convex structures have not yet traversed. The purpose of the candidate borrowing continuation sequence is to change the motion relationship between the silicon sphere to be polished and the polishing pad, so that the local micro-convex structures can enter the missing arc segments as much as possible to complete the continuation. Therefore, the larger the coverage length of the missing arc segment, the more untreated spherical regions the candidate borrowing continuation sequence can compensate for, and the closer the spherical action trajectory formed by the local micro-convex structure is to a complete and continuous state. On the other hand, the length of the bypass arc segment corresponds to the newly added spherical action trajectory formed by deviating from the existing spherical path of the parent arc system during the execution of the candidate borrowing continuation sequence. This part of the action trajectory cannot be used to fill the existing missing arc segments, but instead increases the ineffective polishing area, making... The local micro-convex structure repeatedly acts on non-target spherical positions. Therefore, the length of the missing arc segment reflects the effective continuation ability of the candidate borrowed continuation sequence, while the length of the lateral arc segment reflects the degree of invalid deviation of the candidate borrowed continuation sequence. According to the principle of spherical trajectory optimization, the stronger the effective continuation ability and the smaller the degree of invalid deviation, the closer the corresponding candidate borrowed continuation sequence is to the continuous spherical action trajectory of the parent arc system. Therefore, the missing arc segment coverage length minus the lateral arc segment length is used as the evaluation quantity, which can simultaneously reflect the compensation ability of the candidate borrowed continuation sequence for the missing area and the degree of deviation from the non-target area. The larger the evaluation quantity, the more the candidate borrowed continuation sequence conforms to the spherical continuous extension law of the parent arc system, and the more suitable it is as the optimization object for subsequent collaborative control.

[0058] Based on the evaluation metrics, determine the individual optimal position and the global optimal position; The individual optimal position refers to the position of the particle with the highest evaluation value during the iteration process; the global optimal position refers to the position of the particle with the highest evaluation value for all particles during the iteration process; iterative update refers to the repeated calculation process of adjusting particle position and particle velocity using the individual optimal position and the global optimal position. The positions of all particles formed by the same particle in each iteration are compared with their corresponding evaluation values. The position of the particle with the highest evaluation value is recorded as the individual optimal position of that particle. The individual optimal positions of all particles are compared with their corresponding evaluation values. The individual optimal position with the highest evaluation value is recorded as the global optimal position. The individual optimal position and the global optimal position are written into the iteration data record of the particle swarm algorithm.

[0059] The initial particle swarm is iteratively updated using the individual optimal position and the global optimal position to obtain the particle swarm after the iteration. Each particle in the initial particle swarm is treated as an update object. The update velocity of the particle is calculated according to the initial velocity, current particle position, individual optimal position, and global optimal position. The update velocity is calculated according to the velocity update formula of the particle swarm algorithm. The new position of the particle is calculated using the updated velocity. The candidate borrow continuation sequence corresponding to the updated particle position is recalculated for the vacant arc coverage length, side arc length, and evaluation value. The updated evaluation value is compared with the individual optimal evaluation value saved by the particle. When the updated evaluation value is greater than the individual optimal evaluation value, the individual optimal position is replaced by the updated particle position, and the individual optimal evaluation value is updated at the same time. When the updated evaluation value is not greater than the individual optimal evaluation value, the original individual optimal position and individual optimal evaluation value remain unchanged. Then, the individual optimal evaluation values ​​of all particles are compared, and the global optimal position is updated with the position of the particle with the largest evaluation value. The current particle swarm iteration update is then completed. After completing the current particle swarm iteration update, the current iteration count is incremented by one iteration unit, and the current iteration count is compared with the preset iteration count. If the current iteration count has not reached the preset iteration count, all updated particles are used as the new particle swarm, the updated particle velocities are used as the new particle velocities, and the updated individual optimal positions and global optimal positions are used to continue the next round of particle swarm iteration update. When the current iteration count reaches the preset iteration count, the particle swarm iteration update is stopped, and all particles after the last iteration are used as the particle swarm after the iteration ends. The individual optimal positions, global optimal positions, and evaluation values ​​of each particle are maintained as the basis for obtaining the target borrowed continuation sequence in the future.

[0060] Based on the particle swarm after the iteration, the target borrowing continuation sequence is obtained.

[0061] The particle swarm after iteration refers to the set of all particle data obtained after the iteration update; the target borrowed continuation sequence refers to the candidate borrowed continuation sequence selected from the particle swarm after iteration for subsequent cooperative motion control.

[0062] After the iteration, each particle in the particle swarm is loaded into the result selection process. The final position of each particle is restored to the execution order of the ball attitude switching action, the silicon ball rotation direction alternation action, and the ball relative motion direction rotation action. The restored execution order is used to form the corresponding candidate borrow continuation sequence. The evaluation values ​​of each candidate borrow continuation sequence are compared, and the candidate borrow continuation sequence with the largest evaluation value is saved as the target borrow continuation sequence.

[0063] For example, taking a set of parent arc systems containing parent arc system 1 as an example, parent arc system 1 includes empty arc segment 1, empty arc segment 2, and empty arc segment 3. The length of empty arc segment 1 is 20 micrometers, the length of empty arc segment 2 is 15 micrometers, and the length of empty arc segment 3 is 10 micrometers. After execution, candidate borrowing continuation sequence 1 covers empty arc segment 1 and empty arc segment 2, with a coverage length of 20 micrometers plus 15 micrometers equaling 35 micrometers. After execution, candidate borrowing continuation sequence 1 deviates from the spherical path sequence of parent arc system 1 to form bypass arc segment 1, with a length of 8 micrometers. The evaluation value of candidate borrow continuation sequence 1 is 35 micrometers minus 8 micrometers equals 27 micrometers; after execution, candidate borrow continuation sequence 2 covers missing arc segment 1 and missing arc segment 3, with a missing arc segment coverage length of 20 micrometers plus 10 micrometers equals 30 micrometers. After execution, candidate borrow continuation sequence 2 forms bypass arc segment 2 and bypass arc segment 3, with a length of 4 micrometers for bypass arc segment 2 and a length of 5 micrometers for bypass arc segment 3, resulting in a bypass arc segment length of 4 micrometers plus 5 micrometers equals 9 micrometers. The evaluation value of candidate borrow continuation sequence 2 is 30 micrometers minus 9 micrometers equals 21 micrometers. After the execution of candidate borrowing continuation sequence 3, it covers empty arc segments 2 and 3. The length of the empty arc segment coverage is 15 micrometers plus 10 micrometers, which equals 25 micrometers. After the execution of candidate borrowing continuation sequence 3, it forms bypass arc segment 4, which has a length of 2 micrometers. The evaluation value of candidate borrowing continuation sequence 3 is 25 micrometers minus 2 micrometers, which equals 23 micrometers. Comparing 27 micrometers, 21 micrometers, and 23 micrometers, 27 micrometers is the maximum evaluation value. The particle position corresponding to candidate borrowing continuation sequence 1 is recorded as the global optimal position, and the particle position corresponding to the maximum evaluation value in the evaluation values ​​of the same particle in each iteration is selected as the individual optimal position.

[0064] Obtaining the target borrowing continuation sequence allows subsequent polishing actions to no longer be adjusted solely based on macroscopic process parameters such as pressure and rotation speed. Instead, it directly organizes the switching of the ball-carrying posture, the alternation of the silicon ball's rotation direction, and the rotation of the relative motion direction of the ball around the empty arc segment in the parent arc system. By selecting the action sequence more suitable for continuing the blank spherical area through the coverage length of the blank arc segment and the length of the lateral arc segment, it reduces the situation where the subsequent motion trajectory deviates from the existing spherical action trajectory, improves the compensation targeting of the blank spherical area, and reduces the impact of repeated polishing of non-target areas on surface uniformity.

[0065] S4. Based on the target borrowing continuation sequence, perform coordinated motion control on the silicon ball to be polished and the polishing pad to generate a pose motion combination result; In embodiments of the present invention, generating a pose motion combination result includes: According to the execution order of the ball attitude switching action in the target borrow continuation sequence, control the contact attitude of the silicon ball to be polished relative to the polishing pad. Contact posture refers to the spatial posture of the silicon ball to be polished when it comes into contact with the polishing pad, with the spherical surface of the silicon ball facing the polishing pad. It is used to represent the spherical area of ​​the silicon ball to be polished. The contact posture switching result refers to the change in the contact posture of the silicon ball to be polished relative to the polishing pad after the ball posture switching action is executed according to the target borrow continuation sequence. The execution order of the ball bearing attitude switching action in the target borrow continuation sequence is transmitted to the attitude drive unit of the ball bearing mechanism. The attitude drive unit drives the ball bearing mechanism to change the bearing direction of the silicon ball to be polished according to the execution order, so that different positions on the surface of the silicon ball to be polished face the working surface of the polishing pad in sequence. After each attitude switch, the ball bearing mechanism keeps the silicon ball to be polished in contact with the working surface of the polishing pad. The working surface of the polishing pad continues to bear the chemical mechanical polishing slurry. A corresponding contact attitude is formed between the silicon ball to be polished and the polishing pad, and the result of each contact attitude switch is recorded as contact attitude execution data.

[0066] According to the execution order of the alternating action of the silicon sphere's rotation direction in the target borrow continuation sequence, control the silicon sphere to be polished to switch its rotation direction; The result of the rotation direction switching refers to the change in the rotation direction of the silicon sphere around its own center after the silicon sphere has been rotated alternately according to the target borrowing continuation sequence. The execution order of the alternating rotation direction of the silicon ball in the target borrow continuation sequence is transmitted to the silicon ball rotation drive unit. The silicon ball rotation drive unit drives the silicon ball to be polished to change its rotation direction around its own center according to the execution order, so that the direction of the silicon ball surface passing through the contact area of ​​the polishing pad changes. During the rotation direction switching process, the ball carrier mechanism keeps the silicon ball to be polished in the clamping state, and the polishing pad and the silicon ball to be polished remain in contact. After the rotation direction switching is completed, the result of each rotation direction switching is recorded as rotation direction execution data.

[0067] According to the execution order of the ball-dribble relative motion direction rotation action in the target borrowing continuation sequence, control the switching of relative motion direction between the silicon ball to be polished and the polishing pad; The result of the relative motion direction switching refers to the change in the relative sliding direction between the silicon ball to be polished and the polishing pad after the ball's relative motion direction is rotated according to the target borrowing continuation sequence. The execution order of the ball-carrying mechanism drive unit is transmitted to the polishing pad drive unit and the ball-carrying mechanism drive unit in the target borrow continuation sequence. The polishing pad drive unit changes the movement direction of the polishing pad working surface according to the execution order, and the ball-carrying mechanism drive unit changes the follow-up direction of the silicon ball to be polished on the polishing pad working surface according to the execution order, so that the relative sliding direction between the silicon ball to be polished and the polishing pad is switched. The silicon ball to be polished remains in contact with the polishing pad during the switching process, and the chemical mechanical polishing slurry continues to be located in the contact area between the silicon ball to be polished and the polishing pad. After the relative movement direction is switched, the result of each relative movement direction switch is recorded as relative movement direction execution data.

[0068] The results of switching contact posture, switching rotation direction, and switching relative motion direction are correlated into a pose motion combination result.

[0069] The combined motion result refers to the motion execution result formed by associating the switching results of contact posture, the switching results of rotation direction, and the switching results of relative motion direction according to the execution order in the target borrow continuation sequence. It is used to represent the combined motion state of the silicon ball to be polished, the polishing pad, and the ball carrier mechanism in the chemical mechanical polishing process.

[0070] The contact posture execution data, rotation direction execution data, and relative motion direction execution data are arranged according to the execution order in the target borrow continuation sequence. The contact posture execution data, rotation direction execution data, and relative motion direction execution data belonging to the same execution unit are written into the same combination record. All combination records are written into the same data set according to the execution order, and this data set is recorded as the pose motion combination result.

[0071] By implementing coordinated motion control between the silicon sphere to be polished and the polishing pad, the switching of the sphere's posture, the alternation of the silicon sphere's rotation direction, and the rotation of the sphere's relative motion direction are executed according to the same target sequence. This transforms the action sequence in S3 into actual polishing motion, making the local micro-convex structure more inclined to move along the spherical path corresponding to the parent arc system during subsequent contact, and enter the empty arc segment between adjacent discontinuous short arcs. This reduces the situation where the motion trajectory deviates from the existing spherical action trajectory, reduces the probability of repeated polishing in non-target areas, and allows the pose motion combination result to directly reflect the actual motion state of compensating for the empty spherical area, providing an execution basis for the subsequent formation of coordinated control sequence codes.

[0072] S5. Based on the local micro-convex structure of the polishing pad, define the discontinuous arc mark at the hole edge; based on the combined position and motion results, obtain the collaborative control sequence code corresponding to the discontinuous arc mark at the hole edge, and perform collaborative control on the ball carrier mechanism, the silicon ball to be polished, and the polishing pad.

[0073] In embodiments of the present invention, coordinated control of the ball carrier mechanism, the silicon ball to be polished, and the polishing pad includes: Extract the execution order of ball posture switching actions, the execution order of alternating actions of silicon ball rotation direction, and the execution order of ball dribbling relative motion direction rotation actions from the combined posture motion results; Arrange all combination records in the pose motion combination results according to their generation order. Extract the contact posture execution data recorded in each combination record as ball-carrying posture switching action, extract the rotation direction execution data recorded in each combination record as silicon ball rotation direction alternation action, and extract the relative motion direction execution data recorded in each combination record as dribbling relative motion direction rotation action. Retain the order of the three types of actions in the pose motion combination results to obtain the execution order of ball-carrying posture switching action, silicon ball rotation direction alternation action, and dribbling relative motion direction rotation action.

[0074] The discontinuous short arcs formed by local micro-protrusions on the surface of the silicon sphere to be polished are defined as discontinuous arc marks at the hole edge. Discontinuous arc marks at the edge of the aperture refer to the arc-shaped polishing marks formed by the intermittent contact between the local micro-protrusions at the edge of the micro-aperture of the polishing pad and the surface of the silicon ball to be polished. They are used to characterize the actual trajectory of the local micro-protrusions on the surface of the silicon ball to be polished. The full-surface three-dimensional morphology data of the silicon sphere to be polished after short-range developing chemical mechanical polishing is imported into the arc mark identification process. The discontinuous short arc regions formed by local micro-protrusion structures on the surface of the silicon sphere to be polished are separated from the full-surface three-dimensional morphology data. The spherical position, arc direction and arc length corresponding to the discontinuous short arc regions are used as the descriptive data of the discontinuous short arcs. The discontinuous short arcs are regarded as the discontinuous arc marks at the edge of the holes formed by the action of local micro-protrusion structures at the edge of the micropores of the polishing pad.

[0075] The execution order of the ball attitude switching action, the execution order of the silicon ball rotation direction alternation action, and the execution order of the ball relative motion direction rotation action are sequentially encoded to obtain the collaborative control sequence code corresponding to the discontinuous arc mark on the hole edge. Sequential coding refers to a coding method that assigns consecutive identifiers to each action according to the order in which the actions occur, in order to maintain the sequential relationship between the actions. Cooperative control sequence code refers to a data sequence formed by uniformly encoding the execution order of the ball-carrying posture switching action, the execution order of the alternating action of the silicon ball's rotation direction, and the execution order of the rotating action of the ball's relative motion direction, in order to represent the combined motion relationship between the ball-carrying mechanism, the silicon ball to be polished, and the polishing pad. The execution order of the ball attitude switching action, the execution order of the silicon ball rotation direction alternation action, and the execution order of the ball relative motion direction rotation action are respectively loaded into the encoding process. The three types of execution orders are registered according to the same execution round in the target borrow continuation sequence, so that the ball attitude switching action, rotation direction alternation action, and ball relative motion direction rotation action within the same execution round are in the same encoding position. The ball attitude switching action is written into the attitude field of the encoding position, the silicon ball rotation direction alternation action is written into the rotation field of the encoding position, and the ball relative motion direction rotation action is written into the relative motion field of the encoding position. The attitude field, rotation field, and relative motion field are combined into a single execution encoding unit. All execution encoding units are arranged continuously according to the order of execution rounds. The continuously arranged execution encoding units are encapsulated into a cooperative control sequence code. The cooperative control sequence code is associated with the short arc object corresponding to the discontinuous arc mark on the hole edge, the parent arc system, and the target borrow continuation sequence.

[0076] Based on the collaborative control sequence code, the ball carrier mechanism, the silicon ball to be polished, and the polishing pad are controlled collaboratively.

[0077] The ball carrier mechanism refers to the mechanical actuator used to hold the silicon ball to be polished and drive the silicon ball to complete the attitude adjustment and spatial movement; the coordinated control refers to the combined control process in which the ball carrier mechanism, the silicon ball to be polished and the polishing pad synchronously execute corresponding actions according to the same coordinated control sequence code, so that the contact posture, rotation direction and relative motion direction maintain the corresponding relationship.

[0078] The coordinated control sequence code is sent to the control unit of the chemical mechanical polishing device. The control unit parses each execution code unit sequentially according to the order of execution code units in the coordinated control sequence code. It reads the attitude field in the execution code unit and outputs an attitude switching control command to the ball carrier mechanism, so that the ball carrier mechanism changes the contact attitude of the silicon ball to be polished relative to the polishing pad. It reads the rotation field in the execution code unit and outputs a rotation direction control command to the silicon ball rotation drive unit, so that the silicon ball to be polished changes its rotation direction. It reads the relative motion field in the execution code unit and outputs a relative motion direction control command to the polishing pad drive unit and the ball carrier mechanism drive unit, so that the silicon ball to be polished and the polishing pad change their relative motion direction. After the three types of actions corresponding to the same execution code unit are completed, the control unit calls the next execution code unit, so that the ball carrier mechanism, the silicon ball to be polished, and the polishing pad form a continuous coordinated polishing action according to the coordinated control sequence code.

[0079] Based on the local micro-convex structure of the polishing pad, discontinuous arc marks at the hole edge are defined, and corresponding collaborative control sequence codes are generated according to the combination of pose and motion. This transforms the previously identified discontinuous short arcs, parent arc systems, missing arc segments, and target borrowed continuation sequences into executable control instructions. This enables synchronous control of the ball carrier mechanism, the silicon ball to be polished, and the polishing pad, preventing the local micro-convex structure from randomly sweeping across the silicon ball surface. Instead, it continues the writing according to the target spherical path, reducing the problem of uncovered missing spherical areas and repeated polishing of non-target areas, and improving the uniformity and processing stability of the ultra-smooth surface.

[0080] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for synergistic control of chemical mechanical polishing of ultra-smooth surfaces of millimeter-scale silicon spheres, characterized in that, Includes the following steps: S1. Perform short-range developing chemical mechanical polishing on the silicon sphere to be polished to collect full-surface three-dimensional morphology data of the silicon sphere; generate a short-arc object based on the full-surface three-dimensional morphology data; S2. Based on the extension direction of the short arc corresponding to the short arc object, group short arc objects with the same extension trend into the same short arc group; generate a set of parent arc systems based on the short arc objects, spherical path order and missing arc segments within the same short arc group. S3. Construct the initial particle swarm based on the set of executable actions and the set of parent arc systems of the chemical mechanical polishing device; The initial particle swarm is iteratively updated to obtain the target borrowed continuation sequence; S4. Based on the target borrowing continuation sequence, perform coordinated motion control on the silicon ball to be polished and the polishing pad to generate a pose motion combination result; S5. Based on the local micro-convex structure of the polishing pad, define the discontinuous arc mark at the hole edge; based on the combined position and motion results, obtain the collaborative control sequence code corresponding to the discontinuous arc mark at the hole edge, and perform collaborative control on the ball carrier mechanism, the silicon ball to be polished, and the polishing pad.

2. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 1, characterized in that, Collect full-surface three-dimensional morphology data of the silicon sphere to be polished, including: Identify the local micro-protrusion structure at the edge of the micropores in the polishing pad; The silicon ball to be polished is clamped and the contact between the silicon ball and the polishing pad is controlled. Short-range developing chemical mechanical polishing is performed on the silicon ball to be polished so that the local micro-protrusion structure forms discontinuous short arcs on the surface of the silicon ball to be polished. After short-range developing chemical mechanical polishing, the full-surface three-dimensional morphology data of the silicon sphere to be polished are collected.

3. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 2, characterized in that, Generate short arc objects, including: Extract the spherical position data, arc direction data, and sphere center angle data of discontinuous short arcs from the full-surface three-dimensional topography data; Obtain the radius of the silicon sphere to be polished; Calculate the arc length of the discontinuous short arc based on the radius of the silicon sphere and the central angle of the discontinuous short arc. Associate the spherical position data, arc direction data, and arc length data into a short arc object.

4. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 1, characterized in that, Short arc objects with the same extension trend are grouped into the same short arc group, including: Gather all short arc objects into a short arc set; Based on the spherical position data of the short arc object, determine the starting point and ending point of the short arc object in the spherical coordinates of the silicon sphere to be polished; Based on the arc direction data of the short arc object, determine the extension direction of the short arc corresponding to the short arc object; Based on the starting point, ending point, and extension direction of the short arc, short arc objects with the same extension trend in the short arc set are grouped into the same short arc group.

5. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 1, characterized in that, Generate a set of parent arc systems, including: Based on the starting and ending points of the short arcs of each short arc object in the same short arc group, the spherical path order is arranged for each short arc object in the same short arc group to obtain the spherical path order. Based on the short arc endpoint and short arc start point of two adjacent short arc objects in the same short arc group, generate the missing arc segment between two adjacent short arc objects; Associate the short arc objects, spherical path sequence, and missing arc segments within the same short arc group as a parent arc system; All parent arc systems are combined into a parent arc system set.

6. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 1, characterized in that, Constructing the initial particle swarm includes: Obtain the set of executable actions of the chemical mechanical polishing device; wherein, the set of executable actions includes ball attitude switching action, silicon ball rotation direction alternation action and ball relative motion direction rotation action; Based on the set of executable actions, construct candidate borrowing continuation sequences; The candidate borrowed continuation sequence is used as a particle in the particle swarm algorithm; The initial position of the particle is determined by the execution order of each action in the candidate borrow continuation sequence; The initial velocity of the particle is determined by the execution order of each action in the empty arc segment in the parent arc system set and the candidate borrowed continuation sequence. An initial particle swarm is constructed based on the initial velocity and initial position of the particles.

7. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 6, characterized in that, The target borrow continuation sequence is obtained, including: Based on the empty arc segments in the mother arc system set, obtain the empty arc segment coverage length corresponding to the candidate borrow continuation sequence; Based on the spherical path order in the parent arc system set, obtain the length of the side arc segment corresponding to the candidate borrowed continuation sequence; The evaluation value of the candidate borrowed continuation sequence is calculated based on the coverage length of the missing arc segment and the length of the side arc segment. Based on the evaluation metrics, determine the individual optimal position and the global optimal position; The initial particle swarm is iteratively updated using the individual optimal position and the global optimal position to obtain the particle swarm after the iteration. Based on the particle swarm after the iteration, the target borrowing continuation sequence is obtained.

8. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 2, characterized in that, Generate pose motion combination results, including: According to the execution order of the ball attitude switching action in the target borrow continuation sequence, control the contact attitude of the silicon ball to be polished relative to the polishing pad. According to the execution order of the alternating action of the silicon sphere's rotation direction in the target borrow continuation sequence, control the silicon sphere to be polished to switch its rotation direction; According to the execution order of the ball-dribble relative motion direction rotation action in the target borrowing continuation sequence, control the switching of relative motion direction between the silicon ball to be polished and the polishing pad; The results of switching contact posture, switching rotation direction, and switching relative motion direction are correlated into a pose motion combination result.

9. The method for coordinated control of chemical mechanical polishing of millimeter-scale silicon spheres with ultra-smooth surfaces according to claim 8, characterized in that, Coordinated control of the ball carrier mechanism, the silicon ball to be polished, and the polishing pad, including: Extract the execution order of ball posture switching actions, the execution order of alternating actions of silicon ball rotation direction, and the execution order of ball dribbling relative motion direction rotation actions from the combined posture motion results; The discontinuous short arcs formed by local micro-protrusions on the surface of the silicon sphere to be polished are defined as discontinuous arc marks at the hole edge. The execution order of the ball attitude switching action, the execution order of the silicon ball rotation direction alternation action, and the execution order of the ball relative motion direction rotation action are sequentially encoded to obtain the collaborative control sequence code corresponding to the discontinuous arc mark on the hole edge. Based on the collaborative control sequence code, the ball carrier mechanism, the silicon ball to be polished, and the polishing pad are controlled collaboratively.

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