KR101206778B1 - Carrier head having segmented head covers - Google Patents

Abstract

PURPOSE: A carrier head is provided to prevent the penetration of foreign substances such as an abrasive liquid by including a sealing ring having elasticity between each division cover. CONSTITUTION: A driver(110) is located on the upper side of a carrier head(100). A circular connection base is rotated by being interlocked with the driver. A retainer ring(130) is fixed to the connection base. A head cover(170) includes a first division cover and a second division cover. A partition wall is formed between the first division cover and the second division cover.

Description

Carrier head with split head cover {CARRIER HEAD HAVING SEGMENTED HEAD COVERS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier head of a chemical mechanical polishing apparatus, and more particularly, to a carrier head capable of performing maintenance with less manpower in a shorter time by selecting and maintaining only a corresponding component during maintenance.

The chemical mechanical polishing (CMP) apparatus is a device for performing a wide-area planarization that removes a height difference between a cell region and a peripheral circuit region due to unevenness of a wafer surface generated by repeatedly performing masking, etching, To improve the surface roughness of the wafer due to contact / wiring film separation and highly integrated elements, and the like.

In such a CMP apparatus, a carrier head is used to precisely polish the surface of the wafer by rotating the wafer while applying controllable forces on the wafer. Recently, in order to more precisely control the polishing thickness of the wafer surface, a technique of controlling the pressure for each region of the wafer has been proposed. To this end, since the divided chambers must be formed according to the area of the wafer, a membrane holder for forming the divided chambers and supplying air pressure for each divided chamber is positioned below the center of the carrier head.

Membrane is mainly used as a component that directly or indirectly vacuum-adsorbs or accommodates the wafer while the polishing surface of the wafer faces the polishing pad before and after the polishing process. The carrier head is also provided with a retainer ring that wraps around the wafer to stably hold the wafer in place during the wafer's precision polishing process.

When the carrier head is used in the CMP process for a long time, there is a case where maintenance is required regularly, and there are cases where it is necessary to check the state of a specific component suspected of malfunction of the carrier head. In such a case, conventionally, it has been cumbersome to disassemble the whole carrier head and check for abnormalities of the corresponding parts.

Therefore, there is a problem in that the maintenance of the carrier head takes a long time and wastes excessive cost and manpower. Accordingly, there is an urgent need for a method for maintenance by specific parts.

The present invention has been made in view of the above technical background, and an object of the present invention is to provide a carrier head which can be maintained with less manpower in a shorter time by performing maintenance by selecting only the corresponding parts during maintenance. .

In addition, while the present invention allows to perform maintenance by selecting only the corresponding parts, it is another object to block the foreign matter from penetrating from the outside while the organic bond between each of the components are made to be solid.

In order to achieve the above object, the present invention provides a carrier head for a chemical mechanical polishing apparatus, comprising: a driving body rotatably driven in conjunction with an externally-driven shaft and positioned above the carrier head; An annular connection base rotating in engagement with the driving body; A retainer ring fixed to the connection base; A head cover including a first split cover covering at least a portion of the driving body and a second split cover covering at least a portion of an outer side of the first split cover; Including, the first divided cover and the second divided cover provides a carrier head for a chemical mechanical polishing device, characterized in that configured separately.

Instead of configuring the head cover which encloses the main parts of the carrier head, such as a driving body, a connection base, and a retainer ring, the head is divided into the first divided cover and the second divided cover in the form of a divided cover for each major part of the carrier head. As the cover is configured, the maintenance, repair, and replacement of a specific part can be performed with the cover removed. Through this, maintenance of the carrier head is much simpler than the conventional method of inspecting a specific part by separating from the upper side in order to obtain the effect of reducing the manpower and time.

 At this time, a partition wall protruding from the driving body is formed between the first partition cover and the second partition cover, and the first partition cover and the second partition cover are coupled to the partition wall. Thereby, the position fixing of the 1st divided cover and the 2nd divided cover which are division covers is attained. In addition, when the entire head cover rotates together with the drive body, a problem arises in that stress is concentrated at the position at which the head cover is mounted due to the inertia of the head cover. Since the first split cover and the second split cover are respectively fixed in position, the phenomenon of concentration of stress in the connection portion where the first split cover and the second split cover are fixed by rotational inertia of the carrier head is greatly alleviated. . Thus, the life of the connecting portion of the head cover of the carrier head can be further increased.

The sealing ring is interposed between at least one of the first split cover and the second split cover and the partition wall. Thereby, the inflow of liquid or particles, such as a slurry, is blocked through the connection part of a 1st split cover and a 2nd split cover.

First of all, the first split cover and the second split cover have a handle protruding outward. This makes it possible to easily separate from the carrier head even a divided cover in an area in which the operator pulls the handle to cover only a part of the outer surface of the carrier head.

On the other hand, the head cover may further include a third split cover that covers the central portion of the drive body. The third split cover covering the center portion of the driving body may be fixed in a manner of fitting like the first split cover and the second split cover, but may be fixed to the carrier head by a fastening method such as screws or bolts without being removed. It may be.

In this case, the first divided cover and the third divided cover may be arranged adjacent to each other, and a sealing ring may be interposed between the first divided cover and the third divided cover.

The term 'inside' described in the present specification and claims means a direction from the circumferential surface toward the center of rotation, and the term 'outer' is defined as meaning outward in a radial direction from the center of rotation.

In addition, the term "inner circumferential surface" described in the present specification and claims is defined as a generic term for not only the innermost surface of the annular shape but also an inward facing surface (including a slanting facing surface). . Likewise, the term 'outer circumferential surface' described in the present specification and claims is defined as collectively meaning not only the outermost surface of the annular shape but also the outward facing surface (including the inclined facing surface). "Seal" and similar terms described in this specification and claims are defined in a state in which air cannot pass. The term 'annular' and like terms described in this specification and claims refer to shapes in which trajectories are formed along the circumferential direction with respect to the center of the carrier head.

According to the present invention, instead of the head cover which encloses the main parts of the carrier head, such as the driving body, the connecting base, the retainer ring, etc., the first divided cover, the second divided cover in the form of a divided cover for each of the main parts of the carrier head The head cover is composed of the cover and the third split cover, and when the maintenance of a specific part or area is performed, only the cover of the corresponding position can be separately removed for inspection, repair, and replacement. Compared with the conventional method of checking, the maintenance of the carrier head is much simpler, and the effect of finishing the maintenance of the corresponding parts in a short time can be obtained.

Through this, the present invention can minimize the cost and manpower required for separation and replacement of the carrier head, it is possible to obtain the advantage that the operator's convenience is enhanced.

In addition, the present invention can disassemble and replace parts or areas requiring maintenance even if other components of the carrier head are not unnecessarily dismantled, so that the whole or other parts of the carrier head are conventionally used for inspection of the corresponding parts or areas. Eliminates the need to disassemble extraneous components.

In addition, the present invention is provided with a sealing ring having an elasticity between each of the split cover, not only to maintain the fitted state more firmly by the elastic restoring force of the seal ring at the position where each split cover is fitted, but also CMP process The effect of preventing foreign matters such as slurry and polishing liquid from penetrating into the inside of the carrier head is obtained.

1 is an exploded perspective view of a partially disassembled carrier head according to an embodiment of the present invention
FIG. 2 is an exploded perspective view partially cutting the connecting base and the driving body of FIG. 1; FIG.
3 is a half sectional view of an assembled state of the carrier head of FIG.
4 is an enlarged view of the portion " A "
FIG. 5 is a perspective view illustrating the carrier head with the head cover of FIG. 3 removed. FIG.

Hereinafter, a carrier head 100 according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the subject matter of the present invention.

1 is an exploded perspective view of a partially disassembled carrier head according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of a partially cutaway connection base and a driving body of FIG. 1, FIG. 4 is an enlarged view of portion 'A' of FIG. 3, and FIG. 5 is a perspective view showing the carrier head with the head cover of FIG.

As shown in the figure, the carrier head 100 according to an embodiment of the present invention, the drive body 110 is rotated by an external drive shaft (not shown) to rotate on the upper side of the carrier head, the drive body Connection base 120 is rotated and driven by the connecting pin 160 is rotated to the 110, the annular retainer ring 130 fixed to the lower side of the connection base 120, and the inner peripheral surface of the connection base 120 A plurality of split chambers C1, C2, C3, and C4 are provided in the space between the membrane holder 140 and the membrane holder 140, which are rotated and driven by the receiving portion 142 engaged with the protrusion 122 of the membrane. ) Is formed of a membrane 150 protruding from the plate surface in an annular shape so that a partition wall is formed, and a head cover 170 including a plurality of split covers 171, 172, and 173 to cover the exterior of the carrier head 100. .

Although not shown in the drawing, the driving member 110 is provided with a pneumatic passage through which a plurality of pipes for delivering pneumatics are inserted to transmit pneumatic pressure to various positions, and a rotational torque is transmitted and driven by a driving shaft located outside. .

The connection base 120 is rotated by the rotational force of the drive unit 110 is transmitted by the connection pin 160 penetrates perpendicular to the drive unit 110. At this time, the connecting pin 160 is constrained in the transverse direction, but is not constrained in the up and down direction and is movable up and down.

The connection base 120 includes a lower base 120a coupled to the retainer ring 130 at the lower side, and an upper base 120b configured to press the lower base 120a downward. The upper base 120b is constrained to move upward by the interference with the driving body 110, and the force urging downwards is acted on by the elastic body (not shown) so that the retainer ring 130 is worn to some extent continuously. The ring 130 can be pressed onto the platen pad of the CMP apparatus. An annular sealing ring having a curved cross section is provided between the upper base 120b and the lower base 120a, so that the sealing property can be maintained even if the distance therebetween changes.

As shown in FIG. 2, the lower base 120a is provided with a protrusion 122 protruding inwardly on an inner circumferential surface thereof. The protrusion 122 is inserted into the receiving portion 142 formed on the outer circumferential surface of the membrane holder 140, and when the connection base 120 rotates, the membrane is formed by physical engagement between the protrusion 122 and the receiving portion 142. The holder 140 also rotates together. Therefore, even when the carrier head 100 is used for a long time, since it is not damaged between the connection base 120 and the membrane holder 140, it is preferable in terms of maintenance and continuity of the wafer flat polishing process.

The retainer ring 130 is fixed to the bottom of the connection base 120 by fixing means 99 such as bolts, screws, pins, and the like. Retainer ring 130 is an upper retainer ring 132 formed of a metal material such as stainless steel for use semi-permanently, and polyphenylene sulfide which is durable and chemically inert at the lower side thereof and does not generate cracks even under repeated loads. And a lower retainer ring 131 of PPS) material. The lower retainer ring 131 is formed with a plurality of grooves penetrated in the radial direction so that the slurry flows into the wafer 10 during the CMP process.

The membrane holder 140 is rotated in engagement with the connecting base 120, and a plurality of partition walls 151 are formed at the lower side thereof, and the partition chambers C1, C2, and C3 generated therebetween by the partition walls 151. , An air passage (not shown) for applying pressure to C4 is provided. The partition wall 151 is clamped to the membrane holder 140 to ensure sealing between the adjacent dividing chambers C1, C2, C3 and C4.

Membrane 150 may consist of a single membrane, but consists of an upper membrane that receives air pressure directly within the carrier head 100, and a lower membrane that is indirectly applied to the upper membrane and indirectly pressurized to provide a wafer adsorption surface. Can be.

The connecting pins 160 may be made of a material having excellent durability while having excellent hardness, such as stainless steel. However, when the rotational force is transmitted from the driving unit 110 to the connection base 120 by the connection pins 160 for a long time, the outer circumferential surface of the connection pins 160 is worn and loosened. Since it is expensive to replace the connecting pins 160 every time, the interposing surface of the connecting pins 160 is made of a plastic material that withstands repetitive loads while having a lower hardness than the metal pin body. Cover. As a result, when used for a long time, the metal pin body 161 is not worn, and the interposition pipe 162 is worn, so the metal pin body 161 can be used semi-permanently, and the inexpensive interposition pipe 162 ) Only need to be replaced.

The head cover 170 includes a third split cover 173 surrounding the central portion of the driving body 110, and a center portion 171a contacts the third split cover 173 so as to surround the outer circumferential portion of the driving body 110. The center portion 172a is fitted with a circumferential portion 171b so as to surround the connection base 120 and the first split cover 171 that is fitted and fixed to contact the inner surface of the driving body 110 and the partition wall 110p. The second partition cover 172 is fixed to fit on the outer surface of the partition wall 110p of the 110.

An elastic sealing ring 75 is interposed between the first partition cover 171 and the third partition cover 173, between the partition wall 110p and the first partition cover 171, and between the partition wall 110p and the partition wall 110p. The sealing ring 75 having elasticity is interposed between the second split cover 172. Accordingly, it is possible to maintain the fitted state more firmly by the elastic restoring force of the sealing ring 75 at the position where the respective split covers 171 and 172 are fitted, and the connecting portions 171a and 171b of the split cover 171-173. , 172a is sealed with a sealing ring 75 to prevent foreign substances such as slurry and polishing liquid from penetrating into the carrier head during the CMP process.

The third split cover 173 is detachable by fitting while being fitted to the central protrusion of the driving body 110.

As such, the split covers 171-173 constituting the head cover 170 are detached by a fitting method, so that the first split cover 171 and the driving body 110 covering a portion of the upper side of the driving body 110. The second split cover 172 covering the connection base 120 on the outer side of the outer side, and the third split cover 173 covering the central portion of the drive unit 110. The driving body 110 is a single component, but is surrounded by a different split cover by a central part surrounded by the third split cover 173 and an outer circumferential part surrounded by the first split chamber 171. This is to check the configuration of the gas pipe connected from the outside through the central portion of the drive body 110 and the rotational drive force transmission, while the internal gas pipe of the carrier head 100 through the outer peripheral portion of the drive body 110 This is because the inspection targets are different from each other. Therefore, the present invention may be configured in a form in which two or more split covers 171 and 173 are wrapped even with one component.

Since the cover does not cover the upper and side surfaces of the carrier head 100, but is divided into cover parts 171-173 for each main part, the parts are repaired when a specific part of the carrier head 100 needs to be repaired. Maintenance can be made easier since only the divided cover to be wrapped can be selected for separation and maintenance. In addition, since the first split cover 171 and the second split cover 172 are respectively fixed in position by the partition 110p of the driving body 110 in the form of a split cover, the carrier head 100 rotates. Even during operation, compared with the conventional configuration in which the head cover is formed as one body, the position fixing portions (ie, the center portion and the circle) of the first split cover 171 and the second split cover 172 by the inertial force due to rotation The concentration of stress in the housewife is greatly alleviated. Therefore, the life of the connecting portions 171a, 171b, and 172a of the head cover of the carrier head can be further increased.

Furthermore, radially protruding handles 171n, 172n and 173n are provided on the outside of each of the divided covers 171-173, and the divided covers mounted in a fitting manner by pulling the handles 171n, 172n and 173n outwards. (171-173) can be more easily separated one by one.

On the other hand, in the embodiment shown in the drawing has been taken a configuration in which the plurality of divided cover 170 constituting the head cover 170 by a fitting method as an example, at least a portion of the plurality of divided cover 170 is bolts or pins Bound by also belongs to the scope of the present invention.

The carrier head 100 according to the present invention configured as described above has a first cover 171, a second cover 172, and a third cover which are divided into main cover parts or regions of the carrier head 100. 173), the head cover 170 is configured, and when maintaining a specific part or a specific area, only the cover of the corresponding position can be separated, inspected, repaired, and replaced. Compared to the conventional inspection of the, maintenance of the carrier head 100 is much easier and can achieve the effect of finishing the maintenance of the corresponding parts in a short time.

In addition, since the present invention can disassemble and replace parts or areas requiring maintenance, conventionally, as the whole or other irrelevant components of the carrier head are disassembled for the inspection of the parts or areas, the parts of the parts are removed in the process. Benefits are also obtained that fundamentally solve the problem of possible damage.

The present invention has been exemplarily described through the preferred embodiments, but the present invention is not limited to such specific embodiments, and various forms within the scope of the technical idea presented in the present invention, specifically, the claims. May be modified, changed, or improved.

100: carrier head 110: drive body
120: connection base 120a: upper base
120b: lower base 130: retainer ring
140: membrane holder 150: membrane
160: connecting pin 170: head cover
171: first split cover 172: second split cover
173: 3rd partition cover 171n, 172n, 173n: handle
75: sealing ring with elasticity

Claims (6)

A carrier head for a chemical mechanical polishing apparatus,
A drive body which is rotated in association with an external drive shaft and positioned above the carrier head;
An annular connection base rotating in engagement with the driving body;
A retainer ring fixed to the connection base;
A head cover including a first split cover covering at least a portion of the driving body, and a second split cover covering at least a portion of an outer side of the first split cover;
A partition wall protruding from the driving body between the first split cover and the second split cover;
And the first split cover and the second split cover are coupled to the partition wall, and the first split cover and the second split cover are separately removable. head.
The method of claim 1,
A carrier head for a chemical mechanical polishing apparatus, characterized in that a sealing ring is interposed between at least one of the first divided cover and the second divided cover and the partition wall.
3. The method according to claim 1 or 2,
The first split cover and the second split cover is a carrier head for a chemical mechanical polishing apparatus, characterized in that the handle is formed to protrude outward.
The method of claim 1, wherein the head cover,
And a third split cover covering a central portion of the driving body.
The method of claim 4, wherein
And the first divided cover and the third divided cover are arranged adjacent to each other, and a sealing ring is interposed between the first divided cover and the third divided cover.
A carrier head for a chemical mechanical polishing apparatus,
A drive body which is rotated in association with an external drive shaft and positioned above the carrier head;
An annular connection base rotating in engagement with the driving body;
A retainer ring fixed to the connection base;
A head cover including a first split cover covering at least a portion of the driving body, a second split cover covering at least a portion of an outer side of the first split cover, and a third split cover covering a central portion of the driving body. ;
And the first split cover and the second split cover are separately separable.

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