KR20190036474A - Chemical mechanical planarization membrane - Google Patents

Abstract

In some embodiments, the present disclosure relates to a method of forming a CMP film. This method is performed by providing a malleable material in a cavity in a film mold. The cavity has a central region and a peripheral region surrounding the central region. The malleable material in the cavity is hardened so as to form a film. Curing the malleable material is performed by heating the malleable material in the central region of the film mold to a first temperature and heating the malleable material in the peripheral region of the film mold to a second temperature higher than the first temperature.

Description

{CHEMICAL MECHANICAL PLANARIZATION MEMBRANE}

Reference to Related Application

This application claims priority to U.S. Provisional Patent Application No. 62 / 563,701, filed September 27, 2017, the entire contents of which are incorporated herein by reference.

The integrated chips are constructed using a complex manufacturing process that forms a plurality of different layers on top of each other. A number of different layers are patterned using photolithography, i.e., a process in which the photosensitive material is selectively exposed to electromagnetic radiation. For example, photolithography can be used to define a back end of the line (BEOL) metal interconnect layer formed on top of each other. The electromagnetic radiation is properly focused so as to ensure that the metal interconnect layer is formed with good structural definition. The workpiece may be substantially planar to avoid focusing depth problems so as to properly focus the electromagnetic radiation at the depth of focus. Chemical mechanical planarization (CMP) is a widely used process by which both chemical forces and mechanical forces are used to globally planarize semiconductor workpieces. Planarization prepares the workpiece for the formation of a subsequent layer.

The aspects of the present disclosure are best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that, in accordance with industry standard practice, the various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or decreased for clarity of discussion.
1 illustrates a cross-sectional view of some embodiments of a chemical mechanical planarization (CMP) tool including a carrier including a film having regions with different values of malleability and / or stiffness .
Figure 2 illustrates a plan view illustrating some embodiments of the lower portion of the carrier including a film having regions with different values of stiffness and / or stiffness.
Figures 3A-3C illustrate cross-sectional views illustrating some embodiments of a carrier having a film with regions having different values of stiffness and / or stiffness.
Figures 4A-4C illustrate plan views of some alternative embodiments of the disclosed membrane with regions having different values of stiffness and / or stiffness.
FIG. 5 illustrates a cross-sectional view of some additional embodiments of a CMP tool including a carrier including a film having regions with different values of stiffness and / or stiffness.
Figures 6A-9 illustrate some embodiments of a method of forming a CMP film having regions with different values of stiffness and / or stiffness.
Figure 10 illustrates a flow diagram of some embodiments of a method of forming a CMP film having regions with different values of stiffness and / or stiffness.
11-14 illustrate cross-sectional views of some embodiments of a method for performing a chemical mechanical planarization (CMP) process.
15 illustrates a flow diagram of some embodiments of a method for performing a chemical mechanical planarization (CMP) process.

The following disclosure provides a number of different embodiments or examples for implementing different features of the claimed subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. Of course, these are illustrative only and are not intended to be limiting. For example, in the following description, formation of a first feature on a second feature or on a second feature includes an embodiment wherein the first and second features are formed in direct contact, 2 feature so that the first and second features can not be in direct contact. In addition, the present disclosure may repeat the reference numerals and / or characters in various examples. This repetition is for simplicity and clarity and does not inherently refer to the relationships between the various embodiments and / or configurations discussed.

Also, spatially relative terms such as "below," "below," "lower," "above," "above," and the like refer to one element or feature and another element (s) Or the relationship between the feature (s) and the feature (s). Spatially relative terms are intended to encompass different orientations of a device in use or operation, in addition to the orientation depicted in the Figures. The device may be oriented differently (rotated to 90 degrees or other orientation), and the spatially relative descriptors used herein may be similarly interpreted accordingly.

A chemical mechanical planarization (CMP) process is a process performed by a CMP tool during integrated chip fabrication to form a flat (i.e., planar) surface on which an overlying layer may be formed. The CMP tool typically includes a carrier configured to receive a semiconductor substrate. The carrier includes a film surrounded by a retainer ring. The CMP process can be performed by inserting the substrate into the retainer ring in an upside-down configuration where the backside of the substrate contacts the film. The carrier is subsequently moved to bring the front surface of the substrate into contact with the polishing pad before moving the polishing pad and the carrier relative to each other to polish the front surface of the substrate.

During operation of the CMP tool, the membrane is configured to apply pressure to the backside of the substrate. By adjusting the pressure applied to the back surface of the substrate, the removal rate of the CMP tool can be adjusted (e.g., the greater the pressure applied to the back surface of the substrate, the greater the removal rate). However, it has been recognized that due to the rigidity of the film, the pressure applied by the film to the backside of the substrate may not be uniform. For example, the first pressure that the film applies along the outer edge of the substrate may be less than the second pressure that the film applies to the center of the substrate. The pressure differential applied to the substrate causes the CMP tool to have a lower removal rate along the outer edge of the substrate than at the center of the substrate, resulting in a non-planarity problem on the front side of the substrate.

The present disclosure, in some embodiments, is directed to a method of forming a CMP film configured to mitigate non-uniformity of pressure applied to a substrate during a CMP process, and associated apparatus. The method includes providing a malleable material within a cavity defined by a film mold having a peripheral region surrounding the central region. The malleable material is cured to form a film by heating the malleable material in the central region of the film mold to a first temperature and heating the malleable material in the peripheral region of the film mold to a second temperature higher than the first temperature. The second temperature is configured to provide a peripheral region of the film having a lower stiffness than the central region of the film. The lower stiffness of the peripheral region allows the peripheral region of the film to extend by a larger amount than the central region of the film. The expansion of the peripheral region increases the surface contact between the film and the substrate, thereby increasing the pressure that the film can apply to the periphery of the substrate thereby reducing the non-uniformity of the pressure applied by the film to the substrate.

1 illustrates a cross-sectional view of some embodiments of a chemical mechanical planarization (CMP) tool 100 that includes a carrier including a film having regions with different values of stiffness and / or stiffness.

The CMP tool 100 includes a polishing pad 104 disposed on a platen 102 configured to rotate about a first axis of rotation 106 during operation of the CMP tool 100. The polishing pad 104 includes a roughened upper surface 104u, such as a platen 102, The CMP tool 100 further includes a carrier 108. The carrier 108 is configured to house the substrate 120 in an upside down position such that the front face 120a of the substrate 120 is at the back of the carrier 108. [ During operation, the carrier 108 is configured such that the front face 120a of the substrate 120 contacts the polishing pad 104 while the platen 102 is rotating about the first rotational axis 106. [

The carrier 108 includes a housing 110 coupled to a retainer ring 112. The retainer ring 112 has side walls defining a retainer ring recess configured to receive the substrate 120. The membrane 114 is arranged in the retainer ring recess. The membrane 114 includes a flexible material having a lower surface 114a that faces the housing 110 and an upper surface 114b that faces the housing 110. [ The lower surface 114a is configured to contact the back surface 120b of the substrate 120. [

In some embodiments, the membrane 114 may be coupled to the retainer ring 112 via a support structure 122 disposed between the housing 110 and the membrane 114. The support structure 122 may include internal sidewalls defining a plurality of apertures 124 extending through the support structure 122. A plurality of apertures 124 communicate with one or more chambers 126 disposed between the support structure 122 and the membrane 114, respectively. The one or more chambers 126 are configured to have a pressure set by one or more fluids and / or gases provided through a plurality of apertures 124 via an inlet 128 in the housing 110. The pressure in the one or more chambers 126 applies one or more forces that define the surface profile of the lower surface 114a of the membrane 114. [ In some embodiments, the one or more chambers 126 may comprise a single chamber positioned between the membrane 114 and the support structure 122. In another embodiment (not shown), the one or more chambers 126 may be concentrically divided into a plurality of discrete chambers.

The membrane 114 includes a plurality of forms of the same rope material, each configured to have different values of stiffness and / or stiffness. Different values of stiffness and / or stiffness allow different portions of the membrane 114 to react differently to the applied force. For example, different values of malleability and / or stiffness may be applied to the substrate 120 by the film 114, by allowing different portions of the film 114 to change shapes differently when a force is applied Thereby enabling the pressure to be adjusted. In some embodiments, the malleable material is silicon. In alternative embodiments, the malleable material can be any material that can be formed (e.g., cured) in such a way as to result in different values of stiffness and / or stiffness in different regions of the film.

In some embodiments, the membrane 114 may have a central region 116 and a peripheral region 118 located between the central region 116 and the outermost edge of the membrane 114. The central region 116 comprises a first type of rigid material having a first stiffness and / or a first stiffness, the peripheral region 118 having a second stiffness greater than the first stiffness and / And a second form of the malleable material having the second stiffness. For example, the central region 116 may include a first form of silicon having a lower stiffness than the second form of silicon in the peripheral region 118. [

The greater first stiffness of the central region 116 provides the membrane with sufficient stiffness to allow the membrane 114 to have good control of the pressure applied on the substrate 120. The smaller second stiffness of the peripheral region 118 allows increased expansion of the membrane 114 in the peripheral region 118 when a force is applied to the upper surface 114b of the membrane 114 The membrane 114 in the peripheral region 118 can be expanded by a greater amount than the membrane 114 in the central region 116 when a force is applied to the upper surface 114b of the membrane 114. [ . The expansion of the membrane 114 in the peripheral region 118 increases the surface contact between the membrane 114 and the substrate 120 in the peripheral region 118, Thereby increasing the pressure that can be applied to the substrate 120 in the substrate. By increasing the pressure that the membrane 114 can apply to the substrate 120 in the peripheral region 118, the non-uniformity of the pressure applied to the substrate 120 during the CMP process can be relaxed, Resulting in improved CMP profiles (e.g., smaller height deviations on the substrate) resulting in less rework of the substrate (i.e., improved CMP throughput).

FIG. 2 illustrates a plan view illustrating some embodiments of the lower portion of the carrier 200 including a film having regions with different values of stiffness and / or stiffness.

The carrier 200 includes a retainer ring 112 that extends around the perimeter of the support structure 122. In some embodiments, the lower surface of the retainer ring 112 has a plurality of grooves 202 defined thereon. The plurality of grooves 202 includes a recess in the retainer ring 112 that extends from the inner side wall of the retainer ring 112 to the outer side wall of the retainer ring 112.

The support structure 122 may include internal sidewalls defining a plurality of apertures 124 extending through the support structure 122. The plurality of apertures 124 provide high pressure fluid and / or gas to the upper surface of the membrane 114 arranged between the inner sidewalls of the retainer ring 112 through a plurality of apertures 124 Pressure fluid and / or gas source.

The membrane 114 has a central region 116 having a first stiffness and / or a first stiffness, and a second stiffness surrounding the central region 116 and having a second stiffness greater than the first stiffness, And a peripheral region 118. In some embodiments, the central region 116 may extend from the center of the membrane 114 to a radius R ₁ , while the peripheral region 118 may extend from the center of the membrane 114 from a radius R ₁ to a radius R ₁ + R ₂ . In other embodiments, the central region 116 and / or the peripheral region 118 may extend to different radii. In some embodiments, the radius R ₁ may be greater than the radius R ₂ . In another embodiment, the radius R ₁ may be less than the radius R ₂ . In some embodiments, the membrane 114 may comprise transparent silicon so that the support structure 122 may be visible through the membrane 114.

Figures 3A-3C illustrate cross-sectional views illustrating some embodiments of a carrier having a film comprising regions having different values of stiffness and / or stiffness.

As shown in Figs. 3A-3C, the carrier 108 includes a membrane 114 arranged in a litter inner ring cavity defined by the sidewalls of the retainer ring 112. Fig. The membrane 114 has a central region 116 having a first stiffness and a peripheral region 118 having a second stiffness that is less than the first stiffness. The secondary stiffness of the peripheral region 118 allows the peripheral region 118 to expand and / or compress more than the central region 116 in response to the applied force.

As shown in cross-section 300 of FIG. 3A, before contacting the substrate, the membrane 114 has a bottom surface 114a with a curved profile. In some embodiments, the central region 116 and the peripheral region 118 may extend along a curved profile defined by a continuous function. In another embodiment (not shown), the lower surface 114a may have different curvatures in the central region 116 and in the peripheral region 118. [ For example, the central region 116 and the peripheral region 118 may extend along a curved profile defined by a continuous function. For example, in some embodiments, different values of the stiffness of the central region 116 and the peripheral region 118 may be used for the central region 116 and the peripheral region 118, Resulting in a curvilinear profile defined by an incline that does not converge along the interface between < / RTI >

As the backside 120b of the substrate 120 is brought into contact with the lower surface 114a of the membrane 114 as shown in the cross sectional view 302 of Figure 3b, The shape of the film 114 is modified such that the curved profile of the lower surface 114a is changed to a flat profile along the interface with the back surface 120b of the substrate 120. [ The profile of the peripheral region 118 can also be changed so that it has a first portion that contacts the substrate along a flat profile and a second portion that has a curved profile that separates from the substrate 120 The film 114 will separate from the substrate 120 at a location located within the peripheral region 118).

The membrane 114 contacts the back surface 120b of the substrate 120 along the first section 304. [ Along the first zone 304, the membrane 114 pushes against the backside 120b of the substrate 120 with a force F ₁ . Along the outer edge of the substrate 120, however, the film 114 can not apply a force F ₁ to the backside 120b of the substrate 120, 120 from the rear surface 120b.

Fluid and / or gas is supplied to at least one chamber 126 along the top surface 114b of the membrane 114 via the inlet 128 in the housing 110, as shown in cross-sectional view 306 of Figure 3c. do. The fluid and / or gas increases the pressure along the upper surface 114b of the membrane 114. The pressure causes the peripheral region 118 of the membrane 114 to extend along the lateral direction 308 and along the vertical direction 310. The extension of the peripheral region 118 of the membrane 114 along the lateral direction 308 and along the vertical direction 310 causes an area of surface contact between the membrane 114 and the backside 120b of the substrate 120 . For example, prior to application of pressure (shown in FIG. 3B) to the upper surface of the membrane 114, the membrane 114 contacts the substrate 120 along the first section 304. After application of the pressure to the upper surface 114b of the membrane 114 (shown in Figure 3C), the membrane 114 is exposed to the substrate 120 along a second zone 312 that is larger than the first zone 304 Contact. By increasing the area of contact between the membrane 114 and the backside 120b of the substrate 120, the membrane 114 can increase the application of the force F ₁ along the outer edge of the substrate 120.

By increasing the application of force F ₁ along the outer edge of the substrate 120, the non-uniformity of the pressure applied to the back surface 120b of the substrate 120 is relaxed. The relaxation of the non-uniformity of the pressure applied to the backside 120b of the substrate 120 is dependent on the CMP (CMP) along the edge of the substrate 120, since the pressure applied to the backside 120b of the substrate 120 is proportional to the CMP removal rate. So that the removal rate has a relatively small deviation from the CMP removal rate at the center of the substrate 120. For example, in some embodiments, the 3-sigma deviation of the CMP removal rate may be less than about 10%, while the disclosed film has a variation in the CMP removal rate between the center and edges of the substrate 120 that is less than about 15% . The horseshoe is relatively small (e.g., can be up to 20% or more) as compared to the deviation of the CMP removal rate using a film having consistent stiffness or stiffness over the entire film.

In various embodiments, the shape and / or size of the peripheral region may vary, while still providing increased pressure to the outer edge of the substrate. Figures 4A-4C illustrate plan views of some alternative embodiments of the disclosed membrane with regions having different values of stiffness and / or stiffness.

A top view 400 of FIG. 4A illustrates some embodiments of a film 114 that includes a malleable material. The membrane 114 includes a central region 116 having a first form of rigid material having a first stiffness and a peripheral region 118 having a second form of rigid material having a second stiffness less than the first stiffness . The peripheral region 118 includes a ring extending continuously around the central region 116. In some embodiments, the peripheral region 118 extends radially from the central region 116 of the membrane 114 to the outermost edge (e.g., the edge adjacent the retainer ring 112).

The top view 404 of FIG. 4B illustrates some alternate embodiments of the membrane 114 comprising a malleable material. The membrane 114 includes a central region 116 and a peripheral region 118 including a discontinuous ring disposed between the central region 116 and the outermost edge of the membrane 114. The central region 116 comprises a first form of rigid material having a first stiffness. The discontinuous ring of the peripheral region 118 has discrete segments of a second type of malleable material having a second stiffness that is less than the first stiffness. The discrete segments of the second type of malleable material are separated from each other by the first type of malleable material.

The top view 406 of FIG. 4C illustrates some alternate embodiments of the membrane 114 comprising a malleable material. The membrane 114 includes a central region 116 having a first type of rigid material having a first stiffness, a first peripheral region 118 having a second type of rigid material having a second stiffness that is less than the first stiffness, And a second peripheral region 408 having a third form of roughening material having a third stiffness greater than the second stiffness. In some embodiments, the first stiffness may be substantially the same as the third stiffness. In other embodiments, the first stiffness and the third stiffness may be different. The second peripheral region 408 surrounds the first peripheral region 118 such that the first peripheral region 118 does not extend to the outermost edge 402 of the membrane 114. In some embodiments, the first peripheral region 118 includes a ring that continuously separates the central region 116 from the second peripheral region 408. In another embodiment, the first peripheral region 118 includes a discontinuous ring between the central region 116 and the second peripheral region 408.

FIG. 5 illustrates a cross-sectional view of some additional embodiments of a CMP tool 500 including a carrier including a film having regions with different values of stiffness and / or stiffness.

The CMP tool 500 includes a polishing pad 104 positioned on a platen 102 configured to rotate a polishing pad 104 about a first rotational axis 106 during operation of the CMP tool 500. The pad conditioning element 502 comprising a diamond grit conditioning pad is configured to push the polishing pad 104 with a downward force that causes a plurality of diamond particles to contact the upper surface 104u of the polishing pad 104 . As the polishing pad 104 is rotated by the platen 102, the diamond particles roughen the upper surface 104u of the polishing pad 104 to provide improved mechanical polishing.

The slurry wiring element 504 is arranged on the polishing pad 104. The slurry interconnection element 504 is configured to transfer the slurry compound 506 to the polishing pad 104 during the CMP process. The slurry compound 506 helps remove material from the substrate 120. In some implementations, the composition of the slurry compound 506 may be selected based on the material being removed from the substrate 120. In some embodiments, the substrate 120 includes a semiconductor body as well as a top dielectric material layer (e.g., oxide) and an overlying conductive layer. In some embodiments, the layer of dielectric material may include an oxide (e.g., SiO _2, SiCO, and so on), the conductive layer may include a metal (e.g., copper, aluminum, etc.).

The carrier 108 is configured to hold the substrate 120. The carrier 108 includes a retainer ring 112 coupled to the support structure 122. The retainer ring 112 is used to reduce the lateral movement of the substrate 120 relative to the carrier 108 during the CMP process. In some embodiments, the support structure 122 may be coupled to the retainer ring 112 via a connecting element 512. In some embodiments, the carrier 108 may further include a gimbal element that extends through an opening in the housing 110. The gimbal element 508 is configured to rotate about the second rotational axis 509. In some embodiments, the carrier 108 may further include a ring-shaped base 510 positioned below the housing 110. Clamp ring 514 is coupled to base 510 of ring formation. In some embodiments, the clamp ring 514 is configured to secure the connecting element 512 to the membrane 114. In another embodiment, the clamp ring 514 is configured to secure the connecting element 512 to the support structure 122.

In some embodiments, the clamp ring 514 includes a flexible element surrounding a chamber configured to contain fluid and / or gas. The first gas and / or emulsion source is coupled to the chamber via a first pipe 522. In some embodiments, the first gas and / or fluid source may include a first pump configured to control the pressure in the first pipe 522. In some embodiments, the carrier 108 includes an inner clamp ring 520 coupled to the housing 110 and a ring shaped rolling diaphragm 516 clamped between an outer clamp ring 518 coupled to the base 510, As shown in FIG. The rolling diaphragm 516 seals the space between the housing 110 and the base 510 to define a loading chamber. The second gas and / or fluid source is coupled to the loading chamber via a second pipe 524. In some embodiments, the second gas and / or fluid source may include a second pump configured to control the pressure in the second pipe 524.

6A-9 illustrate some embodiments of a method of forming a film for a CMP tool. The membrane has regions with different values of stiffness and / or stiffness. Although Figures 6A-9 are described with reference to a method, it will be appreciated that the structure shown in Figures 6A-9 is not limited to this method, but rather may be independent of this method.

A malleable material 604 is formed in the cavity 606 defined by the inner surface of the membrane mold 602, as shown in the cross-sectional view 600 of FIG. 6A and the plan view 612 of FIG. 6B. The cavity 606 defined by the membrane mold 602 has a central region 608 and a peripheral region 610 surrounding the central region 608. In some embodiments, the membrane mold 602 may comprise a rigid structure such as, for example, plastic or metal (e.g., aluminum, iron, etc.). In some embodiments, the malleable material 604 may include a fluid that is injected into the cavity 606 defined by the membrane mold 602. For example, in some embodiments, the malleable material 604 is silicon. Silicon has a low cost that allows a low cost film to be formed. In another embodiment, the malleable material 604 can be a similar material that can be cured to achieve different spatial areas with different values of stiffness and / or stiffness.

As shown in cross-sectional view 700 of FIG. 7, a curing process is performed to cure the tortious material (604 of FIG. 6A) to form the film 114. During the curing process, different portions of the malleable material are heated at different temperatures ( T ₁ - T ₂ ). Curing some of the malleable material, such as silicon at different temperatures T ₁ - T ₂ , Silicon) will be cured in different manners, resulting in different regions of the film 114 having different values of malleability and / or stiffness. In some embodiments, the difference in values between the first temperature T ₁ and the second temperature T ₂ is selected to achieve the difference between the central region 116 and the peripheral region 118 (e.g., the first temperature T ₁ and the second temperature T ₂ ) The difference between the second temperature T ₂ is selected to provide less stiffness and / or greater rigidity to the central region 116 than the peripheral region 118). Different values of stiffness in different regions of the membrane 114 allow different regions of the membrane 114 to react differently (e.g., contact or extend) to the force.

For example, in some embodiments, the malleable material in the central region 608 of the membrane mold 602 can be heated to a first temperature T ₁ and the malleable material in the peripheral region 118 of the membrane mold 602 May be heated to a second temperature T ₂ , which is higher than the first temperature T ₁ . The second temperature T ₂ is configured to allow the malleable material in the central region 608 of the film mold 602 to cure in a manner that provides a first stiffness to the central region 116 of the film 114, The temperature T ₂ is configured to allow the malleable material in the peripheral region 610 of the film mold 602 to cure in a manner that provides second stiffness to the peripheral region 118 of the film 114 different from the first stiffness. In some embodiments, the second temperature T ₂ may be as high as about 2 ° Kelvin (K) or more above the first temperature. In another embodiment, the second temperature T ₂ may be greater than the first temperature by an amount greater than about 5 ° K.

It has been recognized that if the stiffness in the central region 116 of the membrane 114 is too low, it is difficult to control the pressure applied to the substrate by the membrane 114. Further, if the stiffness in the peripheral region 118 of the membrane 114 is too high, the membrane 114 will not be malleable enough to apply pressure to the peripheral region of the substrate, and pressure non- something to do. Hardening the malleable material at a lower temperature in the central region 116 therefore provides a higher stiffness to the membrane 114 that allows the membrane 114 to have good control of pressure on the substrate, Curing the malleable material at a higher temperature within the peripheral region 118 provides a lower stiffness to the membrane 114 that allows the membrane 114 to provide good uniformity of pressure on the substrate.

In some embodiments, the difference between the first temperature T ₁ and the second temperature T ₂ can be selected to have a value based on observed differences between CMP removal rates at the center of the substrate and at the edge of the substrate. For example, if it is determined that the removal rate between the central region and the peripheral region of the substrate is 10%, the difference between the first temperature T ₁ and the second temperature T ₂ can be selected to have a value of δ ₁ , If it is determined that the removal rate between the central region and the peripheral region is 20%, the difference between the first temperature T ₁ and the second temperature T ₂ can be selected to have a value of δ ₂ > δ ₁ . By selecting the difference in temperatures based on removal rates, the malleability of the peripheral region 118 can be selected to have a value that minimizes the difference in removal rates between the central region and the peripheral region of the substrate. In some embodiments, the difference between the first temperature T ₁ and the second temperature T ₂ may be determined by an iterative process performed on a plurality of test substrates.

In various embodiments, the different temperatures T ₁ -T ₂ in the central region 608 and the peripheral region 610 of the film mold 602 can be controlled using different heating elements 702. For example, in some embodiments, the temperatures T ₁ -T ₂ in the central region 608 and the peripheral region 610 of the film mold 602 may be controlled using the heating elements 702, . In some embodiments, the heating lamp may be positioned over the film mold 602 such that the radiant heat is in direct contact with the malleable material (e.g., silicon). In another embodiment, the heating lamp may be positioned below the film mold 602 such that radiant heat contacts the film mold 602 along the side opposite the cavity 606. In other implementations, the temperatures in different regions of the film mold 602 may be controlled by heating (e.g., heating) including resistive heating elements and / or water heating elements that contact (e.g., embedded within) Element. ≪ / RTI >

As shown in cross-sectional view 800 of FIG. 8, film 114 is removed from film mold 602 after curing has ended.

Film 114 is attached to carrier 108, as shown in cross-section 900 of Fig. In some embodiments, the membrane 114 may be attached to the carrier 108 by attaching the membrane 114 to a support structure 122 located between the side walls of the retainer ring 112.

FIG. 10 illustrates a flow diagram of some embodiments of a method 100 for forming a CMP film having regions with different values of stiffness and / or stiffness.

Although the disclosed methods (e.g., methods 1000 and 1500) are illustrated and described herein as a series of acts or events, it should be appreciated that the illustrated sequence of events or events should not be construed in a limiting sense. For example, some operations may occur in different orders and / or with other operations or events without departing from the illustrated and / or described aspects. Moreover, not all illustrated acts are required to execute one or more aspects or embodiments described herein. Also, one or more of the operations described herein may be performed in one or more separate operations and / or states.

In operation 1002, a malleable material (e.g., silicon) is provided into the cavity in the membrane mold. FIG. 6 illustrates a cross-sectional view 600 of some embodiments corresponding to operation 1002. FIG.

In operation 1004, the malleable material is cured to form a film by heating different regions of the malleable material to different temperatures. FIG. 7 illustrates a cross-sectional view 700 of some embodiments corresponding to operation 1004.

In some embodiments, the malleable material may be cured according to operations 1006-1008. At operation 1006, the malleable material within the central region of the membrane mold is heated to a first temperature. In operation 1008, the malleable material in the peripheral region of the film mold is heated to a second temperature higher than the first temperature.

In operation 1010, the film is removed from the cavity of the film mold. FIG. 8 illustrates a cross-sectional view 800 of some embodiments corresponding to operation 1010. FIG.

In operation 1012, the film is attached to a CMP carrier. FIG. 9 illustrates a cross-sectional view 900 of some embodiments corresponding to operation 1012. FIG.

In some embodiments, a film attached to the CMP carrier can be used to perform a CMP process on the substrate, and deviations in removal rates achieved by the film between the central region and the peripheral region of the substrate are measured in operation 1014 .

In operation 1016, a deviation may be used to determine a new temperature configured to be used to form an additional film that provides a lower deviation in removal rates. For example, if the membrane is determined to provide a first deviation of removal rates, a first new temperature and a second new temperature may be determined from a first deviation of removal rates, and a removal rate (According to act 1002-1010) that provides a first deviation of the first film thickness (e.g.

Figures 11-14 illustrate cross-sectional views (1100-1400) of some embodiments of a method of performing a chemical mechanical planarization (CMP) process using the disclosed films. Although the cross-sectional views (1100-1400) shown in FIGS. 11-14 are described with reference to a method of performing a chemical mechanical planarization (CMP) process, the structures shown in FIGS. 11-14 are not limited to this method, Lt; / RTI >

The backside 120b of the substrate 120 is brought into contact with the lower surface 114a of the film 114 of the carrier 108, as shown in the cross-sectional view 1100 of Fig. The membrane 114 includes a central region 116 having a first stiffness and a peripheral region 118 having a second stiffness less than the first stiffness. The different values of stiffness provide peripheral area 118 with greater malleability (e.g., the ability to change shape in response to force) than central area 116.

The carrier 120 is placed on the roughened upper surface 104u of the polishing pad 104 on the platen 102 as shown in cross section 1200 of Figure 12, . When the front surface 120a of the substrate 120 is brought into contact with the polishing pad 104, the substrate 120 allows the central region 116 of the film 114 to move along the substantially planar interface of the substrate 120 Pushing the membrane 114 with force, causing it to contact the backside 120b. The peripheral region 118 of the membrane 114 maintains a curved profile that causes the peripheral region 118 of the membrane 114 to be separated from the backside 120b of the substrate 120 by space. As shown in cross-section 1200, the membrane 114 contacts the backside 120b of the substrate along a planar interface with the first zone 304. As shown in FIG.

Fluid and / or gas is supplied to the top surface 114b of the membrane 114, as shown in section 1300 of FIG. The fluid and / or gas increases the pressure along the upper surface 114b of the membrane 114. The pressure causes the peripheral region 118 of the membrane 114 to extend along the lateral direction 308 and along the vertical direction 310. Along the lateral direction 308 and along the vertical direction 310 the expansion of the membrane 114 in the peripheral region 118 increases the second zone 312 along which the membrane 114 contacts the substrate 120 And the rear surface 120b. By increasing the surface contact between the membrane 114 and the backside 120b of the substrate 120, the membrane 114 increases the pressure applied to the backside 120b of the substrate 120 along the periphery of the substrate 120 So as to alleviate the non-uniformity of the pressure applied to the substrate 120.

The polishing pad 104 is moved relative to the substrate 120, as shown in the cross-sectional view 1400 of Fig. Moving the polishing pad 104 relative to the substrate 120 causes the front surface 120a of the substrate 120 to be slowly removed by the roughened upper surface 104u of the polishing pad 104. [ In some embodiments, the platen 102 and the polishing pad 104 may be rotated about a first rotational axis 106 and the carrier 108 and the substrate 120 may be rotated about a second rotational axis 509 .

FIG. 15 illustrates a flow diagram of some embodiments of a method 1500 for performing a chemical mechanical planarization (CMP) process.

At step 1502, the backside of the substrate is brought into contact with the lower surface of the film comprising a central region having a first stiffness and a peripheral region having a second stiffness less than the first stiffness. FIG. 11 illustrates a cross-sectional view 1100 of some embodiments corresponding to operation 1502. FIG.

In operation 1504, the front surface of the substrate is brought into contact with the polishing pad. FIG. 12 illustrates a cross-sectional view 1200 of some embodiments corresponding to operation 1504.

In operation 1506, pressure is applied to the upper surface of the membrane. The pressure causes the peripheral region to expand laterally and vertically, increasing the contact area between the membrane and the backside of the substrate. FIG. 13 illustrates a cross-sectional view 1300 of some embodiments corresponding to operation 1506.

In operation 1508, the substrate is moved relative to the polishing pad to perform a CMP process on the entire surface of the substrate. FIG. 14 illustrates a cross-sectional view 1400 of some embodiments corresponding to operation 1508.

Accordingly, in some embodiments, the present disclosure is directed to a method of forming a CMP film configured to mitigate non-uniformity of pressure applied to a substrate during a CMP process, and associated apparatus.

In some embodiments, the present disclosure is directed to a method of forming a CMP film. The method includes the steps of: providing a malleable material within a cavity of the film mold including a central region and a peripheral region surrounding the central region; And curing the malleable material to form a film, wherein the step of curing the malleable material comprises heating the malleable material within the central region of the film mold to a first temperature; And heating the malleable material within the peripheral region of the film mold to a second temperature higher than the first temperature. In some embodiments, the second temperature is higher than the first temperature by an amount greater than about 2 degrees Kelvin (K). In some embodiments, the peripheral region extends from the central region to the outermost edge of the cavity. In some embodiments, the peripheral region extends as a continuous ring around the central region. In some embodiments, heating the malleable material in the central region to a first temperature and heating the malleable material in the peripheral region to a second temperature are performed by a plurality of heating lamps. In some embodiments, heating the malleable material in the central region to a first temperature and heating the malleable material in the peripheral region to a second temperature are performed by a resistive heating element embedded in the film mold. In some embodiments, the difference between the first temperature and the second temperature is configured to achieve a difference in stiffness or stiffness between a central region of the film and a peripheral region of the film. In some embodiments, the malleable material is comprised of silicon. In some embodiments, the method includes attaching a membrane to a CMP carrier; Performing a CMP process on the substrate using the film; Determining a first deviation of removal rates between a central region of the substrate and a peripheral region of the substrate; And determining a first new temperature and a second new temperature, wherein the first new temperature and the second new temperature are selected such that a second deviation of the removal rates, less than the first deviation of the removal rates, To provide an additional film to provide. In some embodiments, the method further comprises providing additional silicon in the cavity defined by the inner surface of the membrane mold; Heating the additional silicon in the central region of the film mold to a first new temperature; And heating additional silicon in the peripheral region of the film mold to a second new temperature.

In another embodiment, this disclosure is directed to a method of forming a CMP film. The method includes the steps of: providing silicon in a cavity-cavity defined by an inner surface of the mold, the chamber comprising a central region and a peripheral region surrounding the central region; Heating the silicon in the central region of the film mold to a first temperature, wherein the silicon in the central region of the film mold has a first stiffness; And heating the silicon in the peripheral region of the film mold to a second temperature such that silicon in the peripheral region of the film mold has a second stiffness that is less than the first stiffness. In some embodiments, heating the silicon in the central region to a first temperature and the silicon in the peripheral region to a second temperature are performed by a plurality of heating lamps. In some embodiments, the second temperature is higher by about 2 degrees Kelvin (K) than the first temperature. In some embodiments, the peripheral region extends from the central region to the outermost edge of the cavity. In some embodiments, the silicon is transparent. In some embodiments, the peripheral region is a discontinuous ring comprising discrete segments separated by a central region.

In another embodiment, the present disclosure relates to a CMP tool. The CMP tool comprises: a housing; A retainer ring attached to the housing and configured to laterally surround the substrate; And a malleable film having a lower surface to be in contact with a rear surface of the substrate, wherein the malleable film includes a central region having a first rigidity and a first peripheral region surrounding the central region and having a second rigidity smaller than the first rigidity. In some embodiments, the malleable film further includes a second peripheral region separated from the center by the first peripheral region and having a third stiffness that is less than the second stiffness. In some embodiments, the central region comprises a first type of silicon having a first stiffness, the first peripheral region comprises a second type of silicon having a second stiffness, the first type of silicon comprises a second type Lt; RTI ID = 0.0 > of silicon. In some embodiments, the CMP tool further comprises a support structure disposed between the housing and the fusible membrane, wherein the fusible membrane is coupled to the support structure, wherein the support structure includes a plurality of sidewalls defined by sidewalls extending through the support structure ≪ / RTI >

The foregoing description describes features of a number of embodiments to enable those skilled in the art to more fully understand the aspects of the disclosure. Those skilled in the art should appreciate that the present disclosure can readily be used as a basis for designing other processes and structures to accomplish the same purpose of the embodiments disclosed herein and / or to achieve the same advantages. In addition, those skilled in the art should appreciate that equivalent configurations do not depart from the spirit and scope of the present disclosure and that various changes, substitutions and changes can be made without departing from the spirit and scope of the present disclosure.

Examples

Example 1. A method of forming a chemical mechanical planarization (CMP) film,

Providing a malleable material within a cavity in the membrane mold, the cavity including a central region and a peripheral region surrounding the central region; And

Curing the malleable material to form a film

Lt; / RTI >

Wherein the step of curing the malleable material comprises:

Heating the malleable material within the central region of the membrane mold to a first temperature; And

Heating the malleable material within the peripheral region of the film mold to a second temperature higher than the first temperature

(CMP) film. ≪ RTI ID = 0.0 > 11. < / RTI >

Example 2 [0050] In Example 1,

Wherein the second temperature is higher by an amount greater than about 2 degrees Kelvin (K) above the first temperature.

Example 3 In Example 1,

Wherein the peripheral region extends from the central region to an outermost edge of the cavity. ≪ Desc / Clms Page number 17 >

Example 4 In Example 1,

Wherein the peripheral region extends as a continuous ring around the central region. ≪ Desc / Clms Page number 21 >

Example 5 In Example 1,

Wherein the step of heating the volatile material in the central region to a first temperature and the step of heating the volatile material in the peripheral region to a second temperature are performed by a plurality of heating lamps, ).

Example 6 In Example 1,

Heating the volatile material in the central region to a first temperature and heating the volatile material in the peripheral region to the second temperature is performed by a resistive heating element embedded in the film mold Gt; (CMP) < / RTI > film.

[Example 7]

Wherein the difference between the first temperature and the second temperature is configured to achieve a difference in stiffness or rigidity between a central region of the film and a peripheral region of the film.

Example 8 In Example 1,

Wherein the malleable material is comprised of silicon. ≪ RTI ID = 0.0 > 11. < / RTI >

[Example 9] In Example 1,

Attaching the membrane to a CMP carrier;

Performing a CMP process on the substrate using the film;

Determining a first deviation of removal rates between a central region of the substrate and a peripheral region of the substrate; And

Determining a first new temperature and a second new temperature

Further comprising:

Wherein the first new temperature and the second new temperature are configured to be used to form an additional film that provides a second deviation of removal rates less than the first variation of removal rates, ).

Example 10. In Example 9,

Providing additional silicon in the cavity in the membrane mold;

Heating the additional silicon in the central region of the film mold to the first new temperature; And

Heating the additional silicon in the peripheral region of the film mold to the second new temperature

(CMP) < / RTI > film.

Example 11. A method of forming a chemical mechanical planarization (CMP) film,

Providing a cavity within the cavity defined by the inner surface of the membrane mold, the cavity including a central region and a peripheral region surrounding the central region;

Heating the silicon in the central region of the film mold to a first temperature such that the silicon in the central region of the film mold has a first stiffness; And

Heating the silicon in the peripheral region of the film mold to a second temperature such that the silicon in the peripheral region of the film mold has a second stiffness that is less than the first stiffness

Gt; (CMP) < / RTI > film.

[Example 12]

Wherein the step of heating the silicon in the central region to a first temperature and the step of heating the silicon in the peripheral region to a second temperature are performed by a plurality of heating lamps, Lt; / RTI >

Example 13 [0141] In the same manner as in Example 11,

Wherein the second temperature is higher by an amount greater than about 2 degrees Kelvin (K) above the first temperature.

Example 14 [0141] In the same manner as in Example 11,

Wherein the peripheral region extends from the central region to an outermost edge of the cavity. ≪ Desc / Clms Page number 17 >

Example 15. In Example 11,

Wherein the silicon is transparent. ≪ Desc / Clms Page number 24 >

[Example 16]

Wherein the peripheral region is a discontinuous ring comprising discrete segments separated by the central region. ≪ RTI ID = 0.0 > [0002] < / RTI >

Example 17. A chemical mechanical planarization (CMP) tool,

A housing;

A retainer ring attached to the housing and configured to laterally surround the substrate; And

A torsion bar having a lower surface for contacting the back surface of the substrate;

/ RTI >

Wherein the malleable film comprises a central region having a first stiffness and a first peripheral region surrounding the central region and having a second stiffness less than the first stiffness.

Example 18 [0141] In the same manner as in Example 17,

Wherein the malleable film further comprises a second peripheral region separated from the center by the first peripheral region and having a third stiffness less than the second stiffness.

[Example 19]

Wherein the central region comprises silicon of a first type having a first stiffness and the first peripheral region comprises silicon of a second type having a second stiffness,

Wherein the first type of silicon is laterally in contact with the second type of silicon.

20. The process of embodiment 17 wherein,

Further comprising a support structure disposed between the housing and the barrier film, wherein the barrier film is coupled to the support structure, the support structure including a plurality of apertures defined by side walls extending through the support structure (CMP) tool.

Claims (10)

A method of forming a chemical mechanical planarization (CMP) film,
Providing a malleable material within a cavity in the membrane mold, the cavity including a central region and a peripheral region surrounding the central region; And
Curing the malleable material to form a film
Lt; / RTI >
Wherein the step of curing the malleable material comprises:
Heating the malleable material within the central region of the membrane mold to a first temperature; And
Heating the malleable material within the peripheral region of the film mold to a second temperature higher than the first temperature
(CMP) film. ≪ RTI ID = 0.0 > 11. < / RTI > The method according to claim 1,
Wherein the second temperature is higher by an amount greater than 2 degrees Kelvin (K) above the first temperature. The method according to claim 1,
Wherein the peripheral region extends from the central region to an outermost edge of the cavity. ≪ Desc / Clms Page number 17 > The method according to claim 1,
Wherein the peripheral region extends as a continuous ring around the central region. ≪ Desc / Clms Page number 21 > The method according to claim 1,
Heating the malleable material within the central region to a first temperature and heating the malleable material within the peripheral region to a second temperature may include heating the plurality of heating lamps, (CMP) film, wherein the chemical mechanical planarization (CMP) film is performed by at least one of the heating elements. The method according to claim 1,
Wherein the difference between the first temperature and the second temperature is configured to achieve a difference in stiffness or rigidity between a central region of the film and a peripheral region of the film. The method according to claim 1,
Attaching the membrane to a CMP carrier;
Performing a CMP process on the substrate using the film;
Determining a first deviation in removal rate between a central region of the substrate and a peripheral region of the substrate; And
Determining a first new temperature and a second new temperature
Further comprising:
Wherein the first new temperature and the second new temperature are configured to be used to form an additional film that provides a second deviation of the removal rate that is less than the first variation of the removal rate, ). 8. The method of claim 7,
Providing additional silicon in the cavity in the membrane mold;
Heating the additional silicon in the central region of the film mold to the first new temperature; And
Heating the additional silicon in the peripheral region of the film mold to the second new temperature
(CMP) < / RTI > film. A method of forming a chemical mechanical planarization (CMP) film,
Providing a cavity within the cavity defined by the inner surface of the membrane mold, the cavity including a central region and a peripheral region surrounding the central region;
Heating the silicon in the central region of the film mold to a first temperature such that the silicon in the central region of the film mold has a first stiffness; And
Heating the silicon in the peripheral region of the film mold to a second temperature such that the silicon in the peripheral region of the film mold has a second stiffness that is less than the first stiffness
Gt; (CMP) < / RTI > film. In a chemical mechanical planarization (CMP) tool,
A housing;
A retainer ring attached to the housing and configured to laterally surround the substrate; And
A torsion bar having a lower surface for contacting the back surface of the substrate;
/ RTI >
Wherein the malleable film comprises a central region having a first stiffness and a first peripheral region surrounding the central region and having a second stiffness less than the first stiffness.

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