KR102535777B1 - Polishing head and substrate polishing apparatus having the same - Google Patents

Abstract

A polishing head and a substrate polishing apparatus having the polishing head are disclosed. A polishing head of a substrate polishing apparatus includes a polishing pad including a plurality of division pads divided into concentric circles, and the plurality of division pads rotate at different rotational speeds.

Description

Polishing head and substrate polishing apparatus having the same {POLISHING HEAD AND SUBSTRATE POLISHING APPARATUS HAVING THE SAME}

The following embodiments relate to a polishing head having a polishing pad divided into a plurality of regions and a substrate polishing apparatus including the polishing head.

In the manufacture of semiconductor devices, chemical mechanical polishing (CMP) operations including polishing, buffing, and cleaning are required. The semiconductor element is in the form of a multilayer structure, and a transistor element having a diffusion region is formed in a substrate layer. In the substrate layer, connecting metal lines are patterned and electrically connected to transistor elements forming functional elements. As is known, the patterned conductive layer is insulated from other conductive layers with an insulating material such as silicon dioxide. As more metal layers and associated insulating layers are formed, the need to flatten the insulating material increases. Without flattening, the fabrication of additional metal layers becomes substantially more difficult because of the large variation in surface morphology. In addition, the metal line pattern is formed of an insulating material, and excess metal is removed through a substrate polishing operation.

A conventional substrate polishing device is a component for polishing, buffing, and cleaning one or both sides of a substrate, and includes a mechanical polishing member including a belt, polishing pad, or brush, and promotes polishing by chemical components in a slurry solution and strengthened.

On the other hand, in general, a substrate polishing apparatus supplies a slurry containing abrasive particles between a polishing pad attached to a polishing platen and a substrate mounted on a carrier head, and rotates the slurry in the same direction to move the surface between the polishing pad and the substrate. By the relative rotational speed of the substrate surface is flattened and polishing is performed.

The area of the substrate is gradually becoming larger, and in order to match the polishing uniformity during polishing of the large-area substrate, the substrate carrier is divided into several areas and a flexible film is provided to control the amount of polishing by applying different pressures to each area. method is known. However, even if the substrate carrier is divided in this way, there is a limit to constantly maintaining and controlling the uniformity of polishing of the substrate, so a new method of controlling the amount of polishing is required.

Meanwhile, as the size of the substrate increases, various types of polishing pads or polishing heads are used to uniformly polish the substrate. However, it is not easy to uniformly polish a large-area substrate only by enlarging the polishing pad. In addition, when the size of the polishing pad increases in size, a problem in that the polishing uniformity may vary depending on the position within the polishing pad may occur.

According to embodiments, a polishing head having a polishing pad capable of uniformly polishing a substrate and a substrate polishing apparatus including the polishing head are provided.

The tasks to be solved in the embodiments are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

According to embodiments for achieving the above object, a polishing pad having a large area may be formed by dividing a polishing pad into a plurality of parts to form a divided pad. In addition, by rotating the plurality of division pads at different speeds, polishing uniformity can be constantly adjusted and maintained for a large-area substrate. In addition, by forming a plurality of division pads of different materials or having different surface roughness, it is possible to constantly adjust and maintain polishing uniformity for a large-area substrate.

As described above, according to the exemplary embodiments, a polishing pad having a large area can be manufactured by providing a polishing pad divided into a plurality of divided pads, and uniformity of polishing can be maintained for a substrate having a large area. In addition, since the polishing pad is rotated at different speeds depending on the position of the polishing pad or the polishing pad has an area smaller than that of the substrate, it is easy to manufacture and replace the polishing pad.

Effects of the polishing head and the substrate polishing apparatus having the polishing head according to an embodiment are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

The following drawings attached to this specification illustrate a preferred embodiment of the present invention, and together with the detailed description of the present invention serve to further understand the technical idea of the present invention, the present invention is limited to those described in the drawings. It should not be construed as limiting.
1 is a perspective view of a substrate polishing apparatus according to an embodiment.
2 is a perspective view of a polishing head according to an embodiment.
3 is a plan view showing a bottom surface of the polishing head of FIG. 2;
FIG. 4 is a cross-sectional view of the polishing head taken along line AA in FIG. 3 .

Hereinafter, embodiments will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the embodiment, if it is determined that a detailed description of a related known configuration or function hinders understanding of the embodiment, the detailed description will be omitted.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the embodiment. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element may be directly connected or connected to the other element, but there may be another element between the elements. It should be understood that may be "connected", "coupled" or "connected".

Hereinafter, a polishing head 12 having a plurality of divided polishing pads 121 and a substrate polishing apparatus 10 including the polishing pad 121 according to embodiments will be described with reference to FIGS. 1 to 4 .

For reference, FIG. 1 is a perspective view of a substrate polishing apparatus 10 according to an embodiment, FIG. 2 is a perspective view of a polishing head 12 according to an embodiment, and FIG. 3 is a polishing head 12 of FIG. 2 is a plan view showing the bottom surface of the polishing pad 121 side, and FIG. 4 is a cross-sectional view of the polishing head 12 taken along line A-A in FIG. 3 .

Referring to the drawings, the substrate polishing apparatus 10 includes a substrate carrier 11 for supporting a substrate 1, a substrate transfer unit 13 for transferring the substrate 1, and a polishing head provided with a polishing pad 121 ( 12).

The substrate 1 may be a transparent substrate including glass for a flat panel display device (FPD) such as a liquid crystal display (LCD) or a plasma display panel (PDP). However, the substrate 1 is not limited thereto, and may be, for example, a silicon wafer for manufacturing a semiconductor device. In addition, although the substrate 1 is illustrated as having a rectangular shape in the drawings, this is only an example, and the shape and size of the substrate 1 are not limited by the drawings.

In the substrate carrier 11, the substrate 1 is seated so that the surface of the substrate 1 to be polished faces upward. For example, the substrate carrier 11 has a rectangular shape with a larger size than the substrate 1 . Here, the size and thickness of the substrate carrier 11 are only examples, and the shape and size of the substrate carrier 11 are not limited by the drawings.

The substrate carrier 11 may have various structures for seating, mounting, gripping, and/or fixing the substrate 1 thereon. For example, a groove having a predetermined depth in which the substrate 1 is seated may be formed on a surface of the substrate carrier 11 . Alternatively, the substrate carrier 11 may have a suction structure that grips the substrate 1 by providing a vacuum or a suction force to the substrate 1 . For example, a structure such as a hole or a slit for providing a suction force or a vacuum to the substrate 1 may be formed on the surface of the substrate carrier 11 or inside a groove in which the substrate 1 is seated. Alternatively, the substrate carrier 11 may have a structure in which frictional force is generated to prevent the substrate 1 from slipping on a surface on which the substrate 1 is seated, or a separate suction pad to prevent slipping may be provided. Alternatively, the substrate carrier 11 may also have a protruding structure supporting at least a portion of an edge of the substrate 1 . Here, the substrate carrier 11 may have a combination of two or more of the above structures, or may have various shapes for holding or fixing the substrate 1 in addition to the above structures.

The substrate transfer unit 13 transfers the substrate carrier 11 on which the substrate 1 is seated along one direction (eg, the x-axis direction in the drawing), and can continuously transfer a plurality of substrates 1. It has the form of a conveyor or belt.

The substrate conveying unit 13 is composed of a conveying member 130 wound around the outer circumferential surfaces of two driving rollers 131 and 132, and the conveying member 130 continuously rotates by the pair of driving rollers 131 and 132. Accordingly, a plurality of substrate carriers 11 are continuously transported. The substrate transfer unit 13 is formed to a size that allows at least one, preferably a plurality of substrate carriers 11 to be sequentially mounted and transferred.

In addition, the substrate transfer unit 13 has a predetermined length horizontally for transporting the substrate carrier 11 horizontally with respect to the ground surface or the polishing head 12 so that the substrate 1 to be transferred can contact the polishing head 12 horizontally. A transfer section is formed. That is, the upper surface of the substrate transfer unit 13 may be horizontal with a predetermined length and may have an elliptical trajectory when viewed from the side.

According to the embodiment, the substrate transfer unit 13 has a closed-loop conveyor or belt shape, and the substrate carrier 11 is mounted on the transfer member 130 at the beginning of the track of the substrate transfer unit 13, and the substrate 1 Since the loading of the substrate 1 is performed, and the substrate carrier 11 is separated from the transfer member 130 by the rotation of the transfer member 130 at the end of the track, the substrate 1 is unloaded. Unloading is simple and efficient. In addition, throughput may be improved by reducing a lag time caused by loading/unloading of the substrate 1 .

The substrate support unit 14 is provided below the substrate transfer unit 13 and is provided to support the back surface of the substrate carrier 11 with the transfer member 130 interposed therebetween.

The substrate support 14 may be divided into a plurality of regions to support the substrate 1 with different pressures depending on the position of the substrate 1 . In addition, the substrate support 14 may be formed in a size similar to that of the substrate 1 or the substrate carrier 11 so as to stably support the substrate 1 or the substrate carrier 11 . In addition, the substrate support 14 may be formed to have a size equal to or greater than that of the transfer member 130 in the width direction (y-axis direction). However, this is only an example, and the substrate support 14 may have substantially various shapes and sizes capable of supporting the substrate 1 .

The polishing head 12 is provided above the substrate 1, and a polishing pad 121 for polishing the substrate 1 is provided on the lower surface facing the substrate 1. In addition, the polishing head 12 polishes the substrate 1 while moving or rotating on the surface of the substrate 1 .

The polishing head 12 moves linearly and reciprocally along the longitudinal direction (x-axis direction) or width direction (y-axis direction) on the surface of the substrate 1, moves in a zigzag pattern in an oblique line, or moves parallel to the surface of the substrate 1. Any one or more motions among orbital motions or two or more motions may be mixed and driven. Here, the orbit rotation of the polishing head 12 may be a circular orbit rotation or an elliptic orbit rotation around a rotation axis (z-axis direction) passing through the center. In addition, the polishing head 12 operates to reciprocate within a range of a predetermined angle in both directions around the rotation axis. However, this is only an example, and the trajectory linear or zigzag or orbital rotation operation of the polishing head 12 may be substantially changed in various ways.

Here, the substrate polishing apparatus 10 includes a support frame 101 for supporting and transporting the polishing head 12, a fixing frame 102, and a transfer frame 103, and the overall appearance of the substrate polishing apparatus 10 It includes a main frame 100 forming a.

The support frame 101 is provided above the main frame 100 to fix the polishing head 12 and is formed to enable the polishing head 12 to move linearly, zigzagly, and/or orbitally. For example, the support frame 101 is formed at a predetermined height above the substrate transfer unit 13 and is formed across the substrate transfer unit 13 .

The fixed frame 102 is fixed to the polishing head 12, and the other side is coupled to the support frame 101. In addition, the fixing frame 102 is coupled to enable linear movement along the support frame 101 and coupled to enable orbital rotation of the polishing head 12 .

The transfer frame 103 is formed to enable linear movement of the support frame 101 along the transfer direction (x-axis direction) of the substrate 1, and has a predetermined length on both sides of the substrate transfer unit 13 on the main frame 100. is formed In addition, the transfer frame 103 may include an LM guide including rails, gears, ball screws, etc. to enable linear transfer of the support frame 101 . However, this is only an example, and the transport frame 103 may have various shapes capable of transporting the support frame 101 .

Here, the main frame 100, the support frame 101, the fixing frame 102, and the transfer frame 103 show only schematic configurations, and their specific configurations and shapes are not limited by the drawings. In addition, as long as the support frame 101, the fixing frame 102, and the transfer frame 103 can also fix and transport the polishing head 12, their configurations can be substantially changed. In addition, the transfer frame 103 is omitted and the support frame 101 is fixed to the main frame 100 so that the polishing head 12 is formed at a fixed position with respect to the main frame 100 or the substrate transfer unit 13. It is also possible to become

The polishing head 12 is connected to a housing 122 in which the polishing pad 121 is provided, a drive shaft 123 for driving the polishing pad 121, and a drive shaft 123, so that a plurality of drive motors M1 and M2 are connected. , M3) is configured to include a driving unit 120.

The polishing pad 121 is formed in a circular shape smaller than that of the substrate 1 and includes a plurality of concentric divided pads 211 , 212 , and 213 . Here, although the drawing illustrates the three division pads 211, 212, and 213, this is only an example, and the number of division pads 211, 212, and 213 may be substantially varied.

The polishing pad 121 may have a difference in polishing rate between the center and the outermost part. In particular, as the substrate 1 increases in area, the size of the polishing pad 121 also increases. As such, in the large polishing pad 121, a difference in polishing rate may occur depending on its position. In this embodiment, by configuring the plurality of partition pads 211, 212, and 213, it is possible to uniformly polish the substrate 1 by preventing a difference in polishing rate depending on the position.

For example, the plurality of division pads 211, 212, and 213 rotate at different speeds. For example, the polishing rate in the center portion may be increased by rotating the split pad 211 located in the center faster than the split pad 213 located on the outermost side.

Here, the driving shaft 123 is in a one-to-one correspondence with the plurality of divided pads 211, 212, and 213, so that the plurality of hollow shafts 231, 232, and 233 independently rotate each of the divided pads 211, 212, and 213. is formed by Further, a plurality of drive motors M1, M2, and M3 are connected to each of the hollow shafts 231, 232, and 233 to rotate each of the division pads 211, 212, and 213 at a predetermined speed, so that each division pad The speeds of (211, 212, 213) can be rotated independently and differently.

Alternatively, the plurality of division pads 211, 212, and 213 are formed of different materials. For example, since the central division pad 211 is formed of a material having a higher surface roughness than the outermost division pad 213, the polishing rate in the central portion may be increased.

In addition, the plurality of division pads 211, 212, and 213 may have the same or different widths. For example, the plurality of division pads 211, 212, and 213 may be formed to have the same widths W1, W2, and W3. Here, the widths (W1, W2, W3) of the division pads 211, 212, and 213 refer to the radii (R1, R2, R3), but the width of each division pad (211, 212, 213).

Meanwhile, the plurality of division pads 211, 212, and 213 may be formed to have different widths. For example, in the plurality of division pads 211, 212, and 213, the width W3 of the outermost division pad 213 may be smaller than the width W1 of the division pad 211 located in the center. there is. However, this is only an example, and the widths of the division pads 211, 212, and 213 may be substantially changed in various ways.

The polishing pad 121 may be formed with a predetermined interval spaced between the plurality of division pads 211 , 212 , and 213 . A groove having a predetermined depth and width may be formed on the surface of the polishing pad 121 , and the plurality of division pads 211 , 212 , and 213 may be spaced apart from each other with the same width as the groove. However, this is only an example, and it is also possible that the division pads 211, 212, and 213 are formed in close contact with each other without a gap between them. In addition, it is also possible that the interval between the division pads 211, 212, and 213 is wider or narrower than the width of the groove.

According to the present embodiment, the polishing pad 121 is composed of a plurality of split pads 211, 212, and 213, and the rotation speed and/or material of the split pads 211, 212, and 213 are formed differently, thereby polishing. The substrate 1 may be uniformly polished by adjusting the polishing rate according to the position of the pad 121 .

As described above, although the embodiments have been described with limited examples and drawings, those skilled in the art can make various modifications and variations from the above description. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

1: substrate
10: substrate polishing device
100: main frame
101: support frame
102: fixed frame
102: transport frame
11: substrate carrier
12: polishing head
120: drive unit of polishing head
121: polishing pad
211, 212, 213: split pad
122: housing
123, 231, 232, 233: drive shaft
13: substrate transfer unit
130: conveying member
131, 132: drive roller
14: substrate support
M1, M2, M3: drive motor of polishing head
R1, R2, R3: radius of split pad
W1, W2, W3: the width of the split pad

Claims (24)

In the polishing head provided above the substrate and contacting the upper surface of the substrate to polish the substrate,
a polishing pad including a plurality of division pads having the same width; and
a drive shaft having a plurality of hollow shafts corresponding to the plurality of division pads and having different rotational speeds and a plurality of drive motors connected to the plurality of division pads and rotating independently;
to provide,
The polishing head,
Driven by an elliptical orbital rotation motion parallel to the substrate surface within a predetermined angle around the drive shaft on the substrate surface, or driven by a mixed motion of circular orbital rotation and elliptical orbital rotation,
In the plurality of split pads, the rotation speed of the split pad corresponding to the center of the substrate rotates faster than the rotation speed of the split pad corresponding to the edge of the substrate by the plurality of hollow shafts, and the plurality of drive motors A polishing head of a substrate polishing apparatus that rotates independently by
delete delete delete delete According to claim 1,
The polishing head of the substrate polishing apparatus wherein the plurality of dividing pads are formed of different materials.
According to claim 6,
The polishing head of the substrate polishing apparatus, wherein the polishing pad is formed of a material in which the surface roughness of the centrally located dividing pad is greater than the surface roughness of the outermost dividing pad.
According to claim 1,
Grooves are formed on the surface of the polishing pad,
A polishing head of a substrate polishing apparatus in which the plurality of division pads are spaced apart at intervals equal to the width of the groove.
In the polishing head provided above the substrate and contacting the upper surface of the substrate to polish the substrate,
a polishing pad including a plurality of division pads having the same width; and
a drive shaft having a plurality of hollow shafts corresponding to the plurality of division pads and having different rotational speeds and a plurality of drive motors connected to the plurality of division pads and rotating independently;
to provide,
The polishing head,
Driven by an elliptical orbital rotation motion parallel to the substrate surface within a predetermined angle around the drive shaft on the substrate surface, or driven by a mixed motion of circular orbital rotation and elliptical orbital rotation,
In the plurality of split pads, the rotation speed of the split pad corresponding to the center of the substrate rotates faster than the rotation speed of the split pad corresponding to the edge of the substrate by the plurality of hollow shafts, and the plurality of drive motors A polishing head of a substrate polishing apparatus that rotates independently by and is formed of different materials.
According to claim 9,
The polishing head of the substrate polishing apparatus, wherein the polishing pad is formed of a material in which the surface roughness of the centrally located dividing pad is greater than the surface roughness of the outermost dividing pad.
delete delete delete According to claim 9,
Grooves are formed on the surface of the polishing pad,
A polishing head of a substrate polishing apparatus in which the plurality of division pads are spaced apart at intervals equal to the width of the groove.
a substrate carrier on which the substrate is seated so that the polished surface of the substrate faces upward, and a part of the substrate protrudes to support an edge of the substrate;
a substrate conveying unit including a conveying member for conveying the substrate and a pair of driving rollers for driving the conveying member;
a substrate support unit provided inside the substrate transfer unit to support the substrate with respect to the transfer member; and
A polishing pad provided above the substrate transfer unit to polish the substrate and including a plurality of division pads formed to have the same width and a drive shaft, wherein the drive shaft moves the substrate within a predetermined angle around the drive shaft on the surface of the substrate. a polishing head driven by an elliptical orbital rotation motion parallel to the substrate surface or a mixture of circular orbital rotation and elliptical orbital rotation, and provided on an upper portion of the housing to which the polishing pad is attached;
including,
The drive shaft includes a plurality of hollow shafts corresponding to the plurality of divided pads and having different rotational speeds and a plurality of drive motors connected to the plurality of divided pads and rotating independently,
In the plurality of split pads, the rotation speed of the split pad corresponding to the center of the substrate rotates faster than the rotation speed of the split pad corresponding to the edge of the substrate by the plurality of hollow shafts, and the plurality of drive motors A substrate polishing device that rotates independently by
delete delete delete delete According to claim 15,
The plurality of split pads are formed of different materials,
The polishing pad is a substrate polishing apparatus formed of a material in which the surface roughness of the centrally located dividing pad is greater than the surface roughness of the outermost dividing pad.
According to claim 15,
Grooves are formed on the surface of the polishing pad,
A substrate polishing apparatus in which the plurality of division pads are spaced apart at intervals equal to the width of the groove.
delete delete According to claim 15,
The polishing head is a substrate polishing apparatus that is driven to reciprocate linear movement in an x-axis or y-axis direction on the substrate surface or rotate in a circular orbit parallel to the substrate surface.

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