Electroplating coplanarity enhancement with die shield

Abstract

To provide an improved plating system and a plating method which can be used for manufacturing high-quality devices and structures.SOLUTION: An electroplating system comprising a vessel and a paddle disposed within the vessel, the paddle characterized by a first surface and a second surface, the first surface of the paddle including a plurality of ribs extending upwardly from the first surface, wherein the plurality of ribs are arranged substantially parallel around the first surface, the paddle defining a plurality of apertures through the top surface of at least some of the plurality of ribs from the second surface, each of the plurality of apertures having a diameter of 10 mm or less, and the paddle having an open area of 30% or less.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of and priority to U.S. Patent Application No. 17 / 478,252, entitled "ELECTROPLATING CO-PLANARITY IMPROVEMENT BY DIE SHIELDING," filed September 17, 2021, which is incorporated herein by reference in its entirety.

[0002] This technology relates to methods, components, and apparatus for semiconductor manufacturing. More particularly, this technology relates to electroplating components and other semiconductor processing equipment. [Background technology]

[0003] Microelectronic devices, such as semiconductor devices, are fabricated on and / or in wafers or workpieces. A typical wafer plating process involves depositing a metal seed layer on the surface of the wafer via vapor deposition. Photoresist can be deposited and patterned to expose the seed layer. The wafer is then transferred to an electroplating processing chamber, where an electric current is conducted to the wafer through an electrolyte to apply a blanket or patterned layer of metal or other conductive material over the seed layer. Examples of conductive materials include permalloy, gold, silver, copper, cobalt, tin, nickel, and alloys of these metals. Subsequent processing steps form components, contacts, and / or conductive lines on the wafer. Many aspects of the electroplating process can affect process uniformity, including electric field irregularities due to pattern variations, mass transport rates, and other process and component parameters. Even slight discrepancies across the substrate can affect downstream finishing processes. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, there is a need for improved systems and methods that can be used to fabricate high quality devices and structures. These and other needs are addressed by the present technology. [Means for solving the problem]

[0005] An exemplary electroplating system may include a vessel. The system may include a paddle disposed within the vessel. The paddle may be characterized by a first surface and a second surface. The first surface of the paddle may include a plurality of ribs extending upward from the first surface. The plurality of ribs may be disposed generally parallel around the first surface. The paddle may define a plurality of apertures through a thickness of the paddle. Each of the plurality of apertures may have a diameter of less than about 10 mm. The paddle may have an open area of ​​less than about 30%.

[0006] In some embodiments, each of the plurality of apertures can extend from the second surface through a top surface of a respective one of the plurality of ribs. The paddle can include a plurality of vertical partitions extending laterally between each of the plurality of ribs. Each of the plurality of apertures can extend from the second surface through a top surface of each of the plurality of vertical partitions. The paddle can define several slots, openings, or both slots and openings between at least some of the plurality of ribs. The system can include a movable wafer holder for placing the wafer in the container. The distance between the paddle and the surface of the wafer holder can be less than about 10 mm. The location of each of the plurality of apertures can correspond to a dense region of a die pattern used in the electroplating system.

[0007] Some embodiments of the present technology may include a method for electroplating a substrate. The method may include positioning the substrate in contact with a liquid electrolyte in a container. The container may include a die shield disposed between the substrate and one or more anodes. The die shield may define a plurality of open areas between at least one shield area. The plurality of open areas may correspond to dense areas of the substrate. At least one shield area may correspond to a sparse area of ​​the substrate. The method may include conducting an ionic current through the liquid.

[0008] In some embodiments, the method can include identifying a die pattern on the substrate. The die pattern can include a plurality of dense regions and a plurality of sparse regions. The method can include manufacturing a die shield based on the identified die pattern. Manufacturing the die shield can include at least one process selected from the group consisting of 3D printing the die shield, molding the die shield, and machining the die shield. The method can include rotating the substrate while conducting an ionic current through the electrolyte. The method can include adjusting the alignment of the substrate relative to the paddle. The method can include de-plating the substrate in the vessel. The at least one shield region can include a plurality of shield regions. The plurality of opening regions and the plurality of shield regions can be arranged in a repeating pattern around the die shield. The die shield can be incorporated into a weir shield of the vessel.

[0009] Some embodiments of the present technology may include a method for electroplating a substrate. The method may include contacting the substrate with a liquid electrolyte in a container. The method may include conducting an ionic current through the liquid electrolyte. The method may include moving a paddle in a horizontal motion within the liquid electrolyte below the substrate, the paddle selectively shielding a portion of the substrate. The paddle may be characterized by a first surface and a second surface. The first surface of the paddle may include a plurality of ribs extending upward from the first surface. The plurality of ribs may be arranged generally parallel around the first surface. The paddle may define a plurality of apertures through a thickness of the paddle. Each of the plurality of apertures may have a diameter of less than about 10 mm. The paddle may have an open area of ​​less than about 30%.

[0010] In some embodiments, the method can include rotating the substrate while conducting an ionic current through the electrolyte. The method can include adjusting alignment of the substrate with respect to the paddle. The method can include de-plating the substrate in the vessel. The method can include identifying a die pattern on the substrate. The die pattern can include a plurality of dense regions and a plurality of sparse regions. The method can include manufacturing the paddle. Each of the plurality of apertures can be substantially aligned with one of the dense regions. Each of the plurality of apertures can extend from the second surface through a top surface of a respective one of the plurality of ribs. The paddle can include a plurality of vertical partitions extending laterally between each of the plurality of ribs. Each of the plurality of apertures can extend from the second surface through a top surface of a respective one of the plurality of vertical partitions.

[0011] Such technology can provide numerous benefits over conventional systems and techniques. For example, embodiments of the technology can improve coplanarity across a substrate, particularly between areas of the wafer densely populated with pillars and areas sparsely populated with pillars. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the following description and accompanying figures.

[0012] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and drawings. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a top perspective view of an exemplary electroplating system, in accordance with some embodiments of the present technique. [Figure 2] FIG. 2 is a top perspective view of the system of FIG. 1 with the head removed for illustrative purposes. [Figure 3] FIG. 2 is a cross-sectional view of the system of FIG. 1. [Figure 4] 1 is a schematic top view of a die pattern, in accordance with some embodiments of the present technology; [Figure 5] 1 is a schematic top view of an exemplary die shield, in accordance with some embodiments of the present technology; [Figure 6] 1 is a schematic top view of an exemplary paddle, in accordance with some embodiments of the present technology; [Figure 6A] FIG. 7 is a cross-sectional view of the paddle of FIG. 6. [Figure 7] 1 is a cross-sectional view of an exemplary paddle, in accordance with some embodiments of the present technology; [Figure 8] 1A-1C illustrate operations of an exemplary method for electroplating a substrate, in accordance with some embodiments of the present technique. [Figure 9] 1A-1C illustrate operations of an exemplary method for electroplating a substrate, in accordance with some embodiments of the present technique. DETAILED DESCRIPTION OF THE INVENTION

[0014] Some of the figures are included as schematic diagrams. It is understood that the figures are for illustrative purposes and should not be considered to scale unless expressly stated to be to scale. Additionally, as schematic diagrams, the figures are provided to aid in understanding and may not include all aspects or information compared to realistic representations and may include exaggerated material for illustrative purposes.

[0015] In the accompanying drawings, similar components and / or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a letter that distinguishes the similar components. If only a first reference label is used herein, the description is applicable to any one of the similar components having the same first reference label, regardless of the letter.

[0016] In many or most electroplating applications, it is important that the plated metal film or layer have a uniform thickness across the entire wafer or workpiece. Nonuniformity can be caused by irregularities in the electric field due to pattern variations, mass transport rates, and / or other factors. For example, coplanarity issues can arise when a substrate has regions with different densities of vias or pillars. Often, regions with sparser vias and / or pillars exhibit higher plating heights than regions with denser vias and / or pillars. Conventional systems may attempt to improve such coplanarity issues by modifying the chemistry of the electroplating operation, altering deposition and / or mass transport rates, adjusting the conductivity of the electrolytic bath, and / or using multiple chemistries to plate and subsequently de-plate the substrate. However, such operations can add additional complexity, time, and / or cost to the electroplating operation and / or can cause other problems in the electroplating process.

[0017] The present technology overcomes these challenges by incorporating components that selectively shield various regions of a substrate from the electric field generated during an electroplating operation. For example, embodiments of the present technology can utilize a die shield that includes solid shielding regions that match the electric field and shield sparse regions from the electric field, and open regions that allow the electric field to pass through to dense regions of the substrate. Using such a die shield may allow the plating height / rate in dense regions to be maintained while reducing the plating height / rate in the sparse regions. Some embodiments can utilize a paddle that includes open holes aligned with the dense regions of the substrate that allow the electric field to pass through to the dense regions, while the solid surface of the paddle can shield the sparse regions from the electric field. Some embodiments can improve coplanarity by plating and subsequently deplating the substrate in the same chemical bath. Thus, the present technology can improve the coplanarity of a substrate during an electroplating operation.

[0018] While the remainder of the disclosure routinely identifies particular electroplating processes utilizing the disclosed technology, it will be readily understood that the present systems and methods are equally applicable to other plating chambers and systems, and processes such as may occur within the described systems. Accordingly, the present technology should not be considered limited to use with these particular plating processes or systems alone. This disclosure describes one possible system that may include electroplating components according to embodiments of the present technology, before describing further modifications and adaptations to the system according to embodiments of the present technology.

[0019] 1-3 illustrate an exemplary system 10 for electroplating a substrate 30 in accordance with an embodiment of the present technology. The system 10 may include a head 14 supported on a head lifter 16 and a vessel 24. A single system 10 may be used as a standalone unit. Alternatively, multiple systems 10 may be arrayed within an enclosure, with substrates or workpieces being loaded and unloaded from the processor by one or more robots. The head lifter 16 may lift and / or invert the head 14 to load and unload the substrate 300. The head lifter 16 may also lower the head 14 to engage one or more components of the vessel 24 to process the substrate 300. A membrane 40 may be included to divide the vessel 24 into a lower chamber 44 below the membrane 40 containing one or more anodes 28 and a first liquid electrolyte, and an upper chamber 42 containing a second liquid electrolyte. Alternatively, the membrane 40 may be omitted, with the vessel 24 having a single chamber holding a single electrolyte. Referring to the cross-sectional view of Figure 3, a field shaping element 46 made of a dielectric material can be provided within vessel 24. Field shaping element 46 can support membrane 40 and distribute the flow of catholyte. The electric field within vessel 24 can be shaped via an anode shield 45, a chamber shield 47, and / or a weir shield 34. Weir shield 34 can be provided within vessel 24 between paddle 18 and the seal of contact ring 26. The shield can be an annular dielectric element and, together with vessel 24, can provide shielding of the electric field.

[0020] The contact ring 26 may be disposed on the head 14, which can hold the substrate 30. The contact ring 26 may have a plurality of contact fingers for electrically contacting a conductive layer, such as a metal seed layer, on the substrate 30. The contact ring 26 may have a seal 38 for sealing the contact fingers from the electrolyte. The head 14 may include a rotor 36 for rotating the substrate 30 during processing, and the contact ring 26 is on the rotor. Typically, the contact ring may include a seal and a backing plate, and the contact ring and backing plate form a substrate holder. The head 14 may be movable to position the substrate holder at a processing position within the vessel, and the seed layer may be in contact with the electrolyte within the vessel. Electrical controls and power cables (not shown) may be coupled to the lift / rotate weir shield 34 and internal head components, leading from the system 10 to facility connections or connections within a multiprocessor automation system. A rinse assembly 12 having a stepped drain ring may be provided above and / or around the vessel 24.

[0021] The paddle 18 may be provided in a fixed vertical position within the vessel 24 adjacent to the substrate 30. In some embodiments, the paddle 18 may be a generally circular plate of dielectric material having a plurality of parallel ribs or blades spaced apart by slots and / or other openings. A paddle actuator 32 may move the paddle 18 horizontally within the vessel 24 in a plane parallel to the substrate 30 to agitate the electrolyte. The paddle 18 and paddle actuator 32 may be supported on a base plate 20 attached to the vessel 24. The substrate 30 may be rotating or stationary. The slots and / or other openings in the paddle 18 may allow an ion current to pass through the paddle 18.

[0022] In some embodiments, the paddle 18 itself serves as an electric field shield. In typical operation, the paddle 18 can be moved by vibration (which in some embodiments may be 6-10 Hz or approximately 6-10 Hz) with a stroke of approximately 1 / 2 to 1 times the paddle rib pitch. A secondary low-frequency vibration can be used to shift the rib reversal point and avoid imprinting either electric field or mass transfer signatures on the substrate 30 (i.e., stripes on a stationary substrate and rings on a rotating substrate). This secondary vibration is called staggered motion. The envelope of the staggered motion may be approximately equal to the rib pitch. During processing, the paddle actuator 56 moves the paddle 54 to agitate the catholyte contained in the vessel 24. For example, the paddle 18 can move back and forth within the paddle's travel dimension while performing an oscillatory motion. Depending on the application, the paddle 18 can use other motions, such as start / stop or staggered motion.

[0023] FIG. 4 shows a schematic top view of an exemplary substrate 400. The substrate 400 may include several vias or pillars 402, such as copper pillars, that may be formed using an electroplating operation. In some embodiments, the pillars 402 may be arranged around the substrate 400 such that different regions of the substrate 400 have different densities of pillars 402. For example, the substrate 400 may include one or more dense regions 404 that may include a high density of pillars 402 and / or one or more sparse regions 406 that may include a low density of pillars 402. It will be appreciated that some embodiments may include additional regions 408 of intermediate density, and that any number of regions having any number of different densities may be provided on a given substrate 400. Density may be characterized by the number of pillars present within a region of the substrate 400, may be based on the pitch (or distance) between the centers of adjacent pillars 402 within a given region, and / or may be based on the open area within a given region (e.g., the percentage of the area occupied by vias / pillars 402). The regions may be the same size and / or different sizes. The terms "tall," "medium," and "sparse" are understood to be relative terms based on the pillar arrangement of a given substrate 400. For example, a region with a 225 μm pitch between adjacent pillars 402 may be considered dense for a substrate that also includes regions with a 375 μm pitch between adjacent pillars 402, while such a region may be sparse for a substrate that also includes regions with a 150 μm pitch between adjacent pillars 402. During an electroplating operation, different regions of the substrate 400 may experience a higher deposition height than other regions. For example, the dense region 404 may experience a lower deposition height than the medium region 408 and / or the sparse region 406.

[0024] In some embodiments, additional components can be incorporated into an electroplating system to improve the coplanarity of a plated substrate. For example, some electroplating systems, such as, but not limited to, system 10, can include a die shield that selectively shields portions of the substrate from the electric field generated by the anode during a plating operation, reducing the electrodeposition height in selected regions of the substrate, such as sparse regions 406 shown in FIG. 4 above, while leaving the electrodeposition height unchanged in other regions, such as dense regions 404. This can help improve coplanarity across the substrate. FIG. 5 shows a schematic top view of an exemplary die shield 500 in accordance with some embodiments of the present technology. FIG. 5 can show further details regarding components of system 10, such as weir shield 34. The die shield 500 can be positioned within a vessel similar to vessel 24. For example, the die shield 500 can be positioned between the substrate and the anode of the vessel. In some embodiments, the die shield 500 may be coupled to and / or otherwise supported by a dam shield 502, which may be similar to the dam shield 34 described above in connection with FIGS. 1-3. For example, the die shield 500 may span a central opening formed in the dam shield 34, thereby allowing the die shield to be positioned closer to the substrate. The distance between the die shield 500 and the top edge of the paddle (such as the top surface of the ribs of the paddle 18) may be 0.5 mm to 4 mm or about 0.5 mm to 4 mm, 1 mm to 3 mm or about 1 mm to 3 mm, or 1.5 mm to 2 mm or about 1.5 mm to 2 mm. The distance between the die shield 500 and the substrate (such as substrate 30) may be 1 mm to 6 mm or about 1 mm to 6 mm, 2 mm to 5 mm or about 2 mm to 5 mm, or 3 mm to 4 mm or about 3 mm to 4 mm, with the shorter the distance, the more precise the adjustment for shielding the electric field.

[0025] The die shield 500 may be characterized by several shielding regions 504 and several opening regions 506. In some embodiments, all of the shielding regions 504 may be connected by support segments that thread through the opening regions 506. The support segments may be as thin as possible to minimize the shielding effect of the support segments, while remaining thick enough to help maintain sufficient rigidity of the die shield 500 to resist damage or deformation when submerged in a stirred electrolyte. The thickness may depend on the material used to fabricate the die shield 500. To further ensure that the die shield 500 is strong enough to resist damage or deformation during electroplating operations, the die shield 500 may have a thickness of at or about 0.5 mm to 5 mm, at or about 1 mm to 4 mm, or at or about 2 mm to 3 mm. The die shield 500 may be formed from any material that is chemically compatible with the electroplating solution. In some embodiments, the die shield 500 may be formed from a polymer such as acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), thermoplastic polyolefin (TPO), and / or a thermoplastic or other polymer.

[0026] The die shield 500 may be designed for use in plating a particular die pattern. For example, the shield regions 504 may be positioned to align with and / or otherwise correspond to the sparse regions of a given die pattern, while the open regions 506 may be positioned to align with and / or otherwise correspond to the dense regions of a given die pattern. In some embodiments, each shield region 504 may substantially match the size and / or shape of a respective sparse region of the die pattern (e.g., having an area within 20% or about 20%, 15% or about 15%, 10% or about 10%, 5% or about 5%, 3% or about 3%, 1% or about 1%, or less) and / or each open region 506 may substantially match the size and / or shape of a respective sparse region of the die pattern. In other embodiments, the dimensions of the shield regions 504 may be smaller or larger than the dimensions of the corresponding sparse region of the die pattern. For example, the dimensional difference may be at least or about 5%, at least or about 10%, at least or about 15%, at least or about 20%, at least or about 25%, or more. Similarly, the dimensions of the open region 506 may be smaller or larger than the dimensions of the corresponding dense region of the die pattern. For example, the dimensional difference may be at least or about 5%, at least or about 10%, at least or about 15%, at least or about 20%, at least or about 25%, or more. Such a design can account for any lateral spread of the electric field after passing through the die shield. The dimensioning of the shield region 504 and / or the open region 506 may be determined to best account for expected and / or tested differences in deposition height, and in some cases, may account for gradual changes in deposition height between different regions of the die pattern.

[0027] While the shield regions 504 and opening regions 506 are shown arranged in a symmetric, repeating pattern, it will be understood that the arrangement of the shield regions 504 and / or opening regions 506 may be dictated by the particular die pattern and may be non-repeating and / or asymmetric. Additionally, the shield regions 504 and / or opening regions 506 may have a generally rectangular shape, as shown, or other shapes. The use of non-rectangular shapes may be particularly useful when accounting for differences in deposition height within a single region of a die pattern. For example, a die pattern having sparse and dense rectangular regions may exhibit slightly different deposition heights near the edges and / or corners of the rectangular regions, while the central portions of each region may have a fairly consistent deposition height. The shape of the shield regions 504 and / or opening regions 506 may be adjusted in some embodiments to account for such non-uniformities.

[0028] By utilizing a die shield having solid shield regions that coincide with and shield the sparse regions from the electric field and open regions that allow the electric field to pass through to the dense regions of the substrate, embodiments may be able to maintain the plating height / rate in the dense regions while reducing the plating height / rate in the sparse regions. Such a die plate may be used to improve coplanarity of the substrate during electroplating operations.

[0029] As discussed above, some embodiments of the present technology may utilize a paddle to provide some form of electric shielding within an electroplating system. The use of such a paddle as an electric field shielding device may be used in conjunction with or separate from the use of a die shield. FIG. 6 illustrates a schematic top view of an exemplary paddle 600, according to some embodiments of the present technology. FIG. 6 may show further details regarding components within system 10, such as paddle 18. Paddle 600 may be disposed within a vessel similar to vessel 24. In many cases, the distance between paddle 600 and the substrate may be at or about 3 mm to 10 mm, 4 mm to 9 mm, 5 mm to 8 mm, or 5.5 mm to 7 mm, with shorter distances providing more effective shielding and improving precision and adjustability of the electric field shield. Paddle 600 may be characterized by a first surface 602 and a second surface (not shown) opposite first surface 602. The first surface 602 can face the substrate in the electroplating vessel. The first surface 602 can include several ribs 604 extending upward from the first surface 602. For example, the ribs 604 can be parallel to one another or evenly spaced in an array. The distance (or pitch) between adjacent ribs 604 can be at or about 10 mm to 20 mm, at or about 11 mm to 19 mm, at or about 11 mm to 19 mm, at or about 12 mm to 18 mm, at or about 12 mm to 18 mm, at or about 13 mm to 17 mm, at or about 13 mm to 17 mm, at or about 14 mm to 16 mm, or at or about 14 mm to 16 mm, or about 15 mm. In some embodiments, the rib pitch can be determined by a given die pattern. For example, the ribs 604 can be arranged to match (or substantially match) a characteristic length associated with the die pattern, such as the distance between repeated dense regions. The height of each rib may be 5 mm to 15 mm or about 5 mm to 15 mm, 6 mm to 14 mm or about 6 mm to 14 mm, 7 mm to 13 mm or about 7 mm to 13 mm, 8 mm to 12 mm or about 8 mm to 12 mm, 9 mm to 11 mm or about 9 mm to 11 mm, or about 10 mm.In some embodiments, the ends of some or all of the ribs 604 may be open, such that all of the ribs 604 are formed from separate structures, to facilitate drainage. In other embodiments, the ends of some or all of the ribs 604 may be bent, such that all of the ribs 604 are formed from a single, wound structure. In such embodiments, some or all of the ends may define drainage apertures (not shown). In some embodiments, slots and / or other openings (such as those described in connection with paddle 18) may be included in paddle 600, which may increase the conductivity of electrical current through paddle 600. Paddle 600 may be a circular, generally flat dielectric material with an overall thickness of 7-40 mm or about 7-40 mm. Paddle 600 may be generally symmetrical about a centerline parallel to ribs 604. In some embodiments, the second surface of paddle 600 may be flat, while in other embodiments, the second surface may generally mirror first surface 602 and may include some ribs.

[0030] As best shown in FIG. 6A , the paddle 600 can define a plurality of apertures 606 extending through its thickness such that each aperture 606 is generally vertical when the paddle 600 is placed in an electroplating vessel. For example, each aperture 606 can extend from the second surface (which can be a flat portion of the second surface or a distal end of a rib protruding from the second surface) through the top surface of a respective one of the ribs 604. In such embodiments, each rib 604 can include several apertures 606 disposed along its length. In some embodiments, the thickness of each rib 604 can be sufficient to accommodate the diameter of the aperture 606. In other embodiments, as exemplified here, a region of each rib 604 adjacent to the aperture 606 can have a locally increased thickness to accommodate the diameter of the aperture. While the locally increased thickness is shown to be provided as a rectangular prism shape protruding upward along the height of the rib 604, it will be understood that other shapes can be utilized. For example, cylindrical and / or other shapes with tapered sidewalls may be utilized to provide localized thickness increases. In some embodiments, slots and / or other openings (such as those described in connection with paddle 18) may be included in paddle 600, which may increase the conductivity of electrical current through paddle 600.

[0031] In many cases, the apertures 606 can include a circular cross-section, although other cross-sectional shapes are possible in various embodiments. Each of the apertures 606 can have a diameter (or other width dimension) of less than about 10 mm. For example, the diameter may be 0.5 mm to 10 mm or about 0.5 mm to 10 mm, 1 mm to 9 mm or about 1 mm to 9 mm, 2 mm to 8 mm or about 2 mm to 8 mm, 3 mm to 7 mm or about 3 mm to 7 mm, 4 mm to 6 mm or about 4 mm to 6 mm, or about 5 mm. In some embodiments, each aperture 606 may have the same diameter, while in other embodiments, some or all of the apertures 606 may have different dimensions. The apertures 606 may be spaced along the length of each rib 604 at regular and / or irregular intervals. In some embodiments, the distance between adjacent apertures 606 on a given rib 604 (e.g., aperture pitch) may be at or about 10 mm to 20 mm, at or about 11 mm to 19 mm, at or about 11 mm to 19 mm, at or about 12 mm to 18 mm, at or about 12 mm to 18 mm, at or about 13 mm to 17 mm, at or about 13 mm to 17 mm, at or about 14 mm to 16 mm, or at or about 14 mm to 16 mm, or at or about 15 mm. The distance may be measured from the center of adjacent apertures 606. In some embodiments, the distance between apertures 606 along the length of a rib 604 may be the same as the distance between apertures 606 on adjacent ribs 604 (i.e., the pitch of the rib 604), although in other embodiments, these distances may be different. In some embodiments, the aperture pitch may be determined by a given die pattern. For example, the aperture pitch may be arranged to match a characteristic length associated with the die pattern, such as the distance between repeated dense regions.Based on the number, size, and spacing of the apertures 606, the paddle 600 may have a total open area through which the electric field can pass that is less than or about 30%, less than or about 25%, less than or about 20%, less than or about 15%, less than or about 10%, less than or about 5%, less than or about 3%, less than or about 2%, less than or about 1.5%, less than or about 1%, less than or about 0.5%, or less; the lower the percentage of open area of ​​the paddle, the greater the shielding from the electric field.

[0032] As described above, the placement, number, and / or size of the apertures 606 on the paddle 600 may be designed based on a given die pattern. For example, each aperture 606 may be aligned with a portion of a given dense region of the die pattern, with the sparse regions aligned with the solid portions of the paddle 600. The number of apertures 606 aligned with a given dense region may depend on the size and shape of the dense region. Each dense region may be aligned with at least one or about one aperture, at least two or about two apertures, at least three or about three apertures, at least four or about four apertures, or more. In some embodiments, one or more of the apertures 606 may be centrally located along the length of the dense region. In some embodiments, the apertures 606 may be offset from the center of the dense region. For example, apertures 606 may be aligned such that, during agitation of paddle 600, apertures 606 translate relative to the dense region to provide substantially uniform coverage throughout the dense region.

[0033] FIG. 7 is a partial cross-sectional top isometric view of an exemplary paddle 700, in accordance with some embodiments of the present technology. FIG. 7 may show additional details regarding components within system 10, such as paddle 18. Paddle 700 may include similar features to paddle 600. For example, paddle 700 may be characterized by a first surface 702 and a second surface, where one or both of first surface 702 and second surface include a number of ribs 704. Paddle 700 may include a number of vertical dividers 708 extending laterally between adjacent ribs 704. Each of vertical dividers 708 may have a thickness of at or about 1.5 mm to 12 mm, 2 mm to 11 mm, 3 mm to 10 mm, 4 mm to 9 mm, 5 mm to 8 mm, or 6 mm to 7 mm. The pitch between adjacent vertical partitions 708 may be 10 mm to 20 mm or about 10 mm to 20 mm, 11 mm to 19 mm or about 11 mm to 19 mm, 12 mm to 18 mm or about 12 mm to 18 mm, 13 mm to 17 mm or about 13 mm to 17 mm, 14 mm to 16 mm or about 14 mm to 16 mm, or about 15 mm.

[0034] The paddle 700 can define a number of apertures 706 extending through the thickness of the paddle. The apertures 706 can extend from the second surface through the top surface of each of the vertical dividers 708. In some embodiments, each aperture 706 can be centered within the width of the vertical divider 708, while in other embodiments, one or more of the apertures 706 can be offset from the midpoint of the width of the vertical divider 708. Some or all of the apertures 706 can be aligned with one of the ribs 704 and / or offset from the rib 704 (as shown here). In some embodiments, each vertical divider 708 can define at least one drainage aperture extending through the thickness of the vertical divider 708. The drainage apertures can be located between adjacent apertures 706. In some embodiments, slots and / or other openings (such as those described in connection with paddle 18) may be included in paddle 700, which may increase the conductivity of electrical current through paddle 700.

[0035] In many cases, apertures 706 can include a circular cross-section, although other cross-sectional shapes are possible in various embodiments. Each of apertures 706 can have a diameter (or other width dimension) of at or about 0.5 mm to 10 mm, at or about 1 mm to 9 mm, at or about 2 mm to 8 mm, at or about 3 mm to 7 mm, at or about 4 mm to 6 mm, or at or about 5 mm. In some embodiments, each aperture 706 can have the same diameter, while in other embodiments, some or all of apertures 706 can have different dimensions. Apertures 706 can be spaced at regular and / or irregular intervals along the length of each vertical divider 708. In some embodiments, the distance between adjacent apertures 706 on a given vertical partition 708 may be at or about 3 mm to 20 mm, 4 mm to 18 mm, 5 mm to 16 mm, 6 mm to 14 mm, 7 mm to 12 mm, or 8 mm to 10 mm. The distance may be measured from the center of adjacent apertures 706. In some embodiments, the distance between apertures 706 along the length of the vertical partition 708 may be less than the distance between apertures 706 on adjacent vertical partitions 708 (i.e., the pitch of the vertical partitions 708), while in other embodiments, these distances may be the same. In some embodiments, the aperture pitch may be determined by a given die pattern. For example, the aperture pitch may be arranged to match a characteristic length associated with the die pattern, such as the distance between repeated dense regions.Based on the number, size, and spacing of the apertures 606, the paddle 600 may have a total open area through which the electric field can pass that is less than or about 30%, less than or about 25%, less than or about 20%, less than or about 15%, less than or about 10%, less than or about 5%, less than or about 3%, less than or about 2%, less than or about 1.5%, less than or about 1%, less than or about 0.5%, or less; the lower the percentage of open area of ​​the paddle, the greater the shielding from the electric field.

[0036] As described above, the placement, number, and / or size of the apertures 706 on the paddle 700 may be designed based on a given die pattern. For example, each aperture 706 may be aligned with a portion of a given dense region of the die pattern, while the sparse regions are aligned with solid portions of the paddle 700. The number of apertures 706 aligned with a given dense region may depend on the size and shape of the dense region. Each dense region may be aligned with at least one or about one aperture, at least two or about two apertures, at least three or about three apertures, at least four or about four apertures, or more. In some embodiments, one or more of the apertures 706 may be centrally located along the length of the dense region. In some embodiments, the apertures 706 may be offset from the center of the dense region. For example, apertures 706 may be aligned such that, during agitation of paddle 700, apertures 706 translate relative to the dense region to provide substantially uniform coverage throughout the dense region.

[0037] By utilizing a paddle that selectively shields sparse regions from the electric field and apertures that allow the electric field to pass through to dense regions of the substrate, embodiments may allow for maintaining the plating height / rate in dense regions while reducing the plating height / rate in sparse regions. Additionally, translation of the paddle within the vessel may help further improve plating uniformity on the substrate. Thus, such paddles may be used to improve the coplanarity of the substrate during electroplating operations.

[0038] 8 illustrates operations of an exemplary method 800 for electroplating a substrate in accordance with some embodiments of the present technology. The method may be implemented in various electroplating systems, including system 10 described above, which may include a die shield (e.g., die shield 500) and / or paddle (e.g., paddles 600 and 700) in accordance with embodiments of the present technology, such as any of the die shields and / or paddles described above. Method 800 may include several optional operations that may or may not be specifically associated with some embodiments of methods in accordance with the present technology.

[0039] Method 800 may include a processing method that may include operations for electroplating a substrate, such as a semiconductor substrate. The method may include optional operations prior to the start of method 800. For example, in some cases, portions of the electroplating operation may be performed (in the same and / or a different vessel) without a die shield, and the operation may be completed in a vessel with a die shield. The method may include additional operations. For example, method 800 may include operations performed in an order different from that shown. Method 800 may include, in operation 805, positioning a substrate to contact a liquid electrolyte in a vessel. For example, the substrate may be placed in a head and lowered into the electrolyte. The vessel may include a die shield (such as die shield 500) that may be positioned between the substrate and one or more anodes of the electroplating system. The die shield may be designed for a particular die pattern. For example, the die shield may define several opening regions and one or more shield regions, where the opening regions are aligned and / or otherwise coincident with dense regions of the die pattern and the shield regions are aligned and / or otherwise coincident with sparse regions of the die shield.

[0040] In some embodiments, method 800 can include fabricating and / or selecting a die shield for use in electroplating a substrate having a given die pattern (e.g., via and / or pillar placement). For example, a die pattern can be provided and analyzed to identify features of the die pattern. For example, the size, shape, position, density, and / or other characteristics of the die pattern can be identified. Based on the die pattern information, a die shield design can be generated. For example, an electroplating deposition height profile can be modeled based on the size, shape, position, density, and / or other characteristics of the die pattern. Based on the modeled height profile, additional computer modeling can be used to determine the size, shape, and location of several shield and opening regions for the die shield design to ensure uniformity of the predicted deposition height across the substrate. Once designed, the die shield can be manufactured. For example, the die shield may be 3D printed, molded, machined, and / or otherwise manufactured. In some embodiments, the modeling can have enough data to generate an effective die shield design in a single design operation. In other embodiments, the fabricated die shield may be used in several test electroplating operations to determine how effective the die shield design is in improving coplanarity across the substrate. Several iterative steps, including die shield design, fabrication, testing, and refinement, may be performed to design the final die shield to be used in the electroplating operations.

[0041] In operation 810, an ionic current can be conducted through the electrolyte liquid. A paddle of the electroplating system can be translated horizontally within the vessel to agitate the liquid while the ionic current is being conducted. The paddle can be similar to paddle 600 or 700 or any other paddle known in the art. In some embodiments, method 800 can include rotating the substrate while the ionic current is being conducted through the electrolyte. The substrate can be rotated clockwise and / or counterclockwise by any amount, such as 45 degrees, 90 degrees, 120 degrees, 150 degrees, or 180 degrees. Such rotation can be used to align the opening and shield regions with different portions of the substrate, which may allow the rotation of the substrate during the duty cycle to be used as a tuning knob to improve coplanarity across the substrate.

[0042] In some embodiments, the substrate may be de-plated in the same chemical within the vessel. For example, the current waveform may be reversed after a portion of the duty cycle to de-plate high regions (e.g., sparse regions) of the substrate. In some embodiments, this may be done with the substrate in the same orientation relative to the die shield. In other embodiments, the de-plating process may include adjusting the orientation of the substrate relative to the die shield before and / or during application of the de-plating current. For example, the substrate may be in a first orientation relative to the die shield (e.g., with the shield region aligned with the sparse region) for a predetermined portion of the duty cycle (e.g., at or about 50%-99% of the duty cycle, at or about 60%-90% of the duty cycle, or at or about 70%-80% of the duty cycle). This orientation may then be adjusted to a second orientation (e.g., with the shield region aligned with the dense region) to complete the remainder of the duty cycle. This may allow for de-plating of sparse regions and reduce the deposition height in such regions of the substrate, which may help improve co-planarity across the substrate. In some embodiments, the plating current waveform and / or the de-plating current waveform may be synchronized with the translation of the paddle and / or any angular motion (e.g., rotation) of the substrate during the respective processes. The plating current density may be the same as and / or different from the de-plating current density. For example, in some embodiments, the de-plating current density may be higher or lower than the plating current density.

[0043] By utilizing a die shield having solid shield regions that coincide with and shield the sparse regions from the electric field and open regions that allow the electric field to pass through to the dense regions of the substrate, embodiments may be able to maintain the plating height / rate in the dense regions while reducing the plating height / rate in the sparse regions. Such a die plate may be used to improve the coplanarity of the substrate during electroplating operations.

[0044] 9 illustrates operations of an exemplary method 900 for electroplating a substrate according to some embodiments of the present technology. The method may be implemented in various electroplating systems, including system 10 described above, which may include a die shield (e.g., die shield 500) and / or paddle (e.g., paddles 600 and 700) according to embodiments of the present technology, such as any of the die shields and / or paddles described above. Method 900 may include several optional operations that may or may not be specifically associated with some embodiments of methods according to the present technology. Various operations of methods 800 and 900 may be performed in combination.

[0045] Method 900 may include a processing method that may include operations for electroplating a substrate, such as a semiconductor substrate. The method may include optional operations before the start of method 900, or the method may include additional operations. For example, method 900 may include operations performed in an order different from that shown. Method 900 may include, in operation 905, positioning a substrate to contact a liquid electrolyte in a vessel. For example, the substrate may be placed in a head and lowered into the electrolyte. In operation 910, an ionic current may be conducted through the electrolyte liquid. A paddle (such as paddle 600 or 700) of the electroplating system may be translated horizontally within the vessel in operation 915 to agitate the liquid while the ionic current is conducted. The paddle may selectively shield a portion of the substrate from an electric field during the electroplating process. The paddle may be characterized by a first surface and a second surface, and the first surface and / or the second surface may include a plurality of ribs extending upward from the first surface. The ribs may be arranged substantially parallel to the periphery of the first surface. The paddle can define a plurality of apertures through the thickness of the paddle. Each of the plurality of apertures can have a diameter of less than about 5 mm, and the paddle can have an open area of ​​less than about 15%. In some embodiments, the apertures can extend along the height of the ribs, as shown in paddle 600, while in other embodiments, the apertures can extend through vertical partitions extending laterally between the ribs, as shown in paddle 700.

[0046] In some embodiments, the method 900 can include rotating the substrate while the ionic current is conducted through the electrolyte. The substrate can be rotated clockwise and / or counterclockwise by any amount, such as 45 degrees, 90 degrees, 120 degrees, 150 degrees, 180 degrees, etc. Such rotation can be used to align apertures with different portions of the substrate, which may allow the rotation of the substrate during the duty cycle to be used as a tuning knob to improve coplanarity across the substrate.

[0047] In some embodiments, the alignment of the substrate may be adjusted relative to the paddle. For example, the substrate may be rotated and / or otherwise adjusted within the vessel to change the alignment of the apertures. The substrate may be de-plated within the same chemistry within the vessel. For example, the current waveform may be reversed after a portion of the duty cycle to de-plate high (e.g., sparse) regions of the substrate. In some embodiments, this may be done with the substrate in the same orientation relative to the paddle. In other embodiments, the de-plating process may include adjusting the orientation of the substrate relative to the paddle before and / or during application of the de-plating current. For example, the paddle may be in a first orientation (e.g., aligned with the dense aperture regions) for a predetermined portion of the duty cycle (e.g., at or about 50%-99% of the duty cycle, at or about 60%-90% of the duty cycle, or at or about 70%-80% of the duty cycle), and the paddle may be in a first orientation relative to the substrate. This orientation may be adjusted to a second orientation (e.g., aligned with the sparse regions of the apertures), and the remainder of the duty cycle may be completed by reversing the current waveform relative to the current used to plate the substrate. This may allow the sparse regions to be de-plated, reducing the deposition height in such regions of the substrate, which may help improve coplanarity across the substrate. In some embodiments, the plating and / or de-plating current waveforms may be synchronized with the translation of the paddle and / or any angular motion (e.g., rotation) of the substrate during the respective processes. The plating current density may be the same as and / or different from the de-plating current density. For example, in some embodiments, the de-plating current density may be higher or lower than the plating current density.

[0048] In some embodiments, method 900 can include generating and / or selecting a paddle for use in electroplating a substrate having a given die pattern (e.g., via and / or pillar placement). For example, a die pattern can be provided and analyzed to identify die pattern features. For example, the size, shape, location, density, and / or other characteristics of the die pattern can be identified. Based on the die pattern information, a paddle design can be generated. For example, an electroplating deposition height profile can be modeled based on the size, shape, location, density, and / or other characteristics of the die pattern. Based on the modeled height profile, additional computer modeling can be used to determine the size, shape, and location of several apertures for the paddle design to ensure uniformity of the predicted deposition height across the substrate. Once designed, the paddle can be manufactured. For example, the paddle may be manufactured by 3D printing, molding, machining, and / or other methods. In some embodiments, the modeling can have enough data to generate an effective paddle design in a single design operation. In other embodiments, the manufactured paddle may be used in several test electroplating operations to determine how effective the paddle design is in improving coplanarity across the substrate. Several iterative steps, including paddle design, manufacturing, testing, and refinement, may be performed to design the final paddle to be used in the electroplating operations.

[0049] By utilizing a paddle that selectively shields sparse regions from the electric field and apertures that allow the electric field to pass through to dense regions of the substrate, embodiments may allow for maintaining the plating height / rate in dense regions while reducing the plating height / rate in sparse regions. Additionally, translation of the paddle within the vessel may help further improve plating uniformity on the substrate. Thus, such paddles may be used to improve the coplanarity of the substrate during electroplating operations.

[0050] In the foregoing description, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that particular embodiments may be practiced without some of these details or with additional details.

[0051] Although some embodiments have been disclosed, those skilled in the art will recognize that various modifications, alternative structures, and equivalents can be used without departing from the spirit of the embodiments. In addition, some well-known processes and elements have not been described to avoid unnecessarily obscuring the technology. Therefore, the above description should not be interpreted as limiting the scope of the technology.

[0052] Where a range of values ​​is provided, unless the context clearly indicates otherwise, it is understood that each intervening value, to the smallest fraction of the unit of the lower limit, between the upper and lower limits of that range is also specifically disclosed. Any narrower range between any stated or unstated intervening value in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of these smaller ranges may or may not independently be included within the range, and each range in which either limit, neither limit, or both limits are included within the smaller range is also encompassed within the scope of the technology, subject to any specifically excluded limits within the stated range. If a stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

[0053] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to "a region" includes a plurality of such regions, reference to "the aperture" includes a reference to one or more apertures and equivalents thereof known to those skilled in the art, and so forth.

[0054] Additionally, the words "comprise(s)", "comprising", "contain(s)", "containing", "include(s)", and "including", when used in this specification and the claims that follow, are intended to specify the presence of stated features, integers, components, or operations, but they do not exclude the presence or addition of one or more other features, integers, components, operations, acts, or groups.

Claims

1. A container and a paddle disposed within the vessel; 1. An electroplating system comprising: the paddle is characterized by a first surface and a second surface, the first surface of the paddle including a plurality of ribs extending upwardly from the first surface; the plurality of ribs are arranged generally parallel around the first surface; the paddle defining a plurality of apertures through a thickness of the paddle; each of the plurality of apertures having a diameter of less than about 10 mm; the paddle having an open area of ​​less than about 30%; Electroplating system.

2. each of the plurality of apertures extending from the second surface through a top surface of a respective one of the plurality of ribs; The electroplating system of claim 1 .

3. the paddle comprising a plurality of vertical partitions extending laterally between each of the plurality of ribs; The electroplating system of claim 1 .

4. each of the plurality of apertures extending from the second surface through a top surface of a respective vertical partition of the plurality of vertical partitions; The electroplating system of claim 3 .

5. the paddle defining a number of slots, openings, or both slots and openings between at least some of the plurality of ribs; The electroplating system of claim 1 .

6. a wafer holder movable to position a wafer within the vessel, the distance between the paddle and a surface of the wafer holder being less than about 10 mm; The electroplating system of claim 1 further comprising:

7. the location of each of the plurality of apertures corresponds to a dense region of a die pattern used in the electroplating system; The electroplating system of claim 1 .

8. positioning a substrate in contact with a liquid electrolyte in a container; the enclosure comprising a die shield disposed between the substrate and one or more anodes; the die shield defines a plurality of open areas between at least one shield area; the plurality of open regions correspond to dense regions of the substrate; the at least one shielding region corresponds to a sparse region of the substrate; Positioning and conducting an ionic current through said liquid; 1. A method of electroplating a substrate, comprising:

9. identifying a die pattern of the substrate, the die pattern including a plurality of dense regions and a plurality of sparse regions; manufacturing the die shield based on the identified die pattern; The method of electroplating a substrate of claim 8 further comprising:

10. manufacturing the die shield comprises at least one process selected from the group consisting of 3D printing the die shield, molding the die shield, and machining the die shield; 10. A method for electroplating a substrate according to claim 9.

11. rotating the substrate while the ionic current is conducted through the electrolyte. The method of electroplating a substrate of claim 8 further comprising:

12. adjusting the alignment of the substrate relative to the die shield; deplating the substrate in the vessel; The method of electroplating a substrate of claim 8 further comprising:

13. the at least one shielding region includes a plurality of shielding regions; the plurality of opening regions and the plurality of shielding regions are arranged in a repeating pattern around the die shield. A method for electroplating a substrate according to claim 8.

14. the die shield is integrated into the vessel weir shield; A method for electroplating a substrate according to claim 8.

15. contacting the substrate with a liquid electrolyte in a container; conducting an ionic current through the liquid electrolyte; moving a paddle in a horizontal motion within the liquid electrolyte beneath the substrate to selectively shield portions of the substrate; the paddle is characterized by a first surface and a second surface, the first surface of the paddle including a plurality of ribs extending upwardly from the first surface; the plurality of ribs are arranged generally parallel around the first surface; the paddle defining a plurality of apertures through a thickness of the paddle; each of the plurality of apertures having a diameter of less than about 5 mm; the paddle having an open area of ​​less than about 15%; To move and 1. A method of electroplating a substrate, comprising:

16. rotating the substrate while the ionic current is conducted through the electrolyte. The method of electroplating a substrate of claim 15 further comprising:

17. adjusting the alignment of the substrate relative to the paddle; deplating the substrate in the vessel; The method of electroplating a substrate of claim 15 further comprising:

18. identifying a die pattern of the substrate, the die pattern including a plurality of dense regions and a plurality of sparse regions; manufacturing the paddle, wherein each of the plurality of apertures is substantially aligned with one of the dense regions; The method of electroplating a substrate of claim 15 further comprising:

19. each of the plurality of apertures extending from the second surface through a top surface of a respective one of the plurality of ribs; 16. A method for electroplating a substrate according to claim 15.

20. the paddle comprising a plurality of vertical partitions extending laterally between each of the plurality of ribs; each of the plurality of apertures extending from the second surface through a top surface of a respective vertical partition of the plurality of vertical partitions; 16. A method for electroplating a substrate according to claim 15.

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