JP6494910B2 - Enhanced electrolyte hydrodynamics for efficient mass transport during electroplating - Google Patents

Description

This application is based on US Provisional Patent Application No. 61 / 736,499 entitled Attorney Docket No. LAMRP 015 P, filed Dec. 12, 2012, entitled "Enhanced Electrolyte Fluid Dynamics for Efficient Material Transport During Electroplating". The above application is incorporated by reference in its entirety for all purposes. This application is also a continuation-in-part of US patent application Ser. No. 13 / 893,242 (Attorney Docket No. NOVLP367X1), filed May 13, 2013, entitled “ Cross-flow manifold for electroplating apparatus”. No. 13 / 172,642, filed on Jun. 29, 2011, entitled "Control of Electrolyte Fluid Dynamics for Efficient Material Transport During Electroplating". This is a continuation-in-part application of US Provisional Patent Application No. 61/61, filed October 21, 2010, entitled "Flow distribution and flow shaping plate for electroplating cells". No. 405608 (Attorney Docket No. NOVLP 396 P); filed on August 18, 2010 entitled "High-flow process for wafer level packages. U.S. Provisional Patent Application No. 61 / 374,911 (Attorney Docket No. NOVLP 367P); and U.S. Provisional Patent Application No. 61 / 361,333 (Attorney Docket No.) filed on July 2, 2010, entitled "An inclined HRVA" Claiming the benefit of the priority of NOVLP 366 P), each of which is incorporated herein by reference in its entirety for all purposes. Further, U.S. patent application Ser. No. 13 / 893,242 is directed to U.S. Provisional Patent Application No. 61 / 646,598 (Attorney Docket No. NOVLP 367 X1 P) entitled " Cross-flow Manifold for Electroplating Apparatus" filed May 14, 2012. It claims the benefit of priority and the above application is incorporated herein in its entirety for all purposes.

  Embodiments disclosed herein relate to methods and apparatus for controlling the fluid dynamics of an electrolyte during electroplating. More particularly, the methods and apparatus described herein are particularly convenient for metal plating on semiconductor wafer substrates, particularly semiconductor wafers having a plurality of recessed features. Exemplary processes and features include, for example, small microbump resistive through plating features (e.g., of copper, nickel, tin and tin alloy solders) having widths less than about 50 [mu] m, and copper through silicon vias (TSVs) It may have features.

  Electrochemical deposition processes are well established in modern integrated circuit fabrication. The aluminum-to-copper migration of metal wire interconnects at the beginning of the 20th Century has led to a significant increase in the demand for sophisticated electrodeposition processes and plating tools. Most of this refinement has evolved in response to the demand for smaller conductive lines in the metallization layer of the device. Such copper wires are formed by electroplating metal in very thin, high aspect ratio trenches and vias in a methodology (pre-passivated metallization) commonly referred to as "damascene" processing.

  Electrochemical deposition can now meet the market demand for sophisticated packages and multiple chip interconnect technologies, commonly known as wafer level package (WLP) and through silicon via (TSV) electrical connection technology It has become. These techniques generally have significant challenges, due in part to large feature sizes and high aspect ratios (compared to interconnects in transistor process (FEOL)).

  Depending on the type and application of the package features (e.g. chip-to-chip or chip-to-chip junctions such as through chip vias TSVs, interconnect redistribution interconnects, or flip chip pillars), the current technology is that of the features to be plated. The major dimensions will usually be greater than about 2 μm, typically about 5 to 100 μm (eg, copper pillars can be about 50 μm). For some on-chip structures, such as power busses, the features to be plated can be larger than 100 μm. The aspect ratio of WLP features can be as high as about 2: 1 (height: width), but is typically about 1: 1 or less, while the TSV structure has a very high aspect ratio ( For example, about 20: 1).

  When scaling down the size of the WLP structure from 100-200 μm to less than 50 μm (eg 20 μm), this scale shows the size of the feature and the typical mass transport boundary layer thickness (the distance at which convective transport to a flat surface occurs) Because they are approximately equal, a unique set of problems occur. In the case of the production with a large conventional feature, the convective transport of fluid and material to the feature has been caused by the penetration of the flow field into the feature as a whole, but in the case of a small feature The formation of flow vortices and stagnation can impede the speed and uniformity of mass transport within the growing feature. Thus, there is a need for new methods to create very uniform mass transport within small "microbumps" and TSV features.

  Not only the size of the feature but also the plating rate distinguishes between WLP and TSV applications and damascene applications. In many WLP applications, depending on the metal to be plated (eg copper, nickel, gold, silver solder etc), for example for capital productivity of wafer patterns that are variable, and targets for in-die and feature There is a balance between manufacturing requirements and cost requirements, as well as technical requirements and technical difficulties, with respect to wafer requirements at an intern level. In the case of copper, this balance is usually achieved at a rate of at least about 2 μm / min, typically at least about 3 to 4 μm / min or more. In the case of tin and tin alloy plating, plating rates greater than about 3 μm / min and in some applications at least about 7 μm / min may be required. For nickel and gold strike plating (e.g., low concentration gold flash film layers), the plating rate may be about 0.1 to 1.5 [mu] m / min. In these regimes of high plating rates associated with metals, efficient mass transport of metal ions in the electrolyte to the plated surface is important.

  In certain embodiments, good plating uniformity within the wafer (WIW uniformity), good plating uniformity within and between all features of a particular die (WID uniformity), and individual features themselves In order to achieve good plating uniformity (WIF uniformity) within, it is necessary to plate in a very uniform manner across the surface of the wafer. The high plating rates in WLP and TSV applications have challenges with respect to the uniformity of the electrodeposited layer. For various WLP applications, plating has a half range variation of less than about 5% along the diameter of the wafer surface (this is called WIW non-uniformity, which is a single die within the die). It is necessary to indicate that the features are measured at multiple locations across the diameter of the wafer for certain types. Similarly, equally difficult requirements include different sizes (eg, feature diameters) or feature densities (eg, whether features are isolated or embedded in the center of the array of chip dies). There is a uniform deposition (thickness and shape) of different features. This performance specification is commonly referred to as WID non-uniformity. WID non-uniformity may be due to local variability of various types of features as described above (e.g., variation in the range of <5% by half) and specific locations on the wafer (e.g. Measured as the ratio of the average height or other dimensions of the features in the die of a given wafer at the edge die).

  Another difficult requirement is the general control of feature geometry. Without proper control of flow and mass transport convection, after plating, the lines or pillars will be convex, flat or concave in two or three dimensions (eg saddle or dome shape) but always Although generally flat contours are preferred. While addressing these difficulties, WLP applications must compete with traditional, inherently inexpensive pick and place serial routing tasks. In addition, electrochemical deposition for WLP applications can be performed using lead, tin, tin-silver and other under bump meta such as nickel, cobalt, gold, palladium and their various alloys (some of which include copper). It may require the plating of various metals other than copper, such as solder of metallization (UBM) material. Plating of tin-silver near eutectic alloys is an example of a plating technique for alloys used for plating as lead-free solders that are alternatives to lead-tin eutectic solders.

Embodiments described herein relate to methods and apparatus for electroplating a material on a substrate. In general, the techniques disclosed herein provide an improved channeled ion having a plurality of through holes adapted to transport ions through plating, and a series of ridges or steps to improve plating uniformity. With the use of resistive elements. In one aspect of the embodiment, an electroplating apparatus comprising: (a) an electroplating chamber configured to include an electrolyte and an anode during electroplating of a metal on a substantially flat substrate; (b B.) A substrate holder configured to hold a substantially flat substrate such that the plated surface of the substrate is separated from the anode during electroplating; (c) an ion resistant element; i) a plurality of channels extending through the ion resistant element adapted to transport ions through the ion resistant element during electroplating; (ii) substantially parallel to the plating surface of the substrate Ionic resistance, comprising: a substrate facing side separated from the plated surface of the substrate and the air gap; and (iii) a plurality of ridges positioned on the substrate facing side of the ion resistant element (d) is an electrolyte transverse flow of the air gap; sexual element For input, the inlet to the air gap; and to receive a transverse flow of electrolyte through the (e) the air gap, comprising an outlet of the air gap, the electroplating apparatus is provided wherein, during the electroplating The inlet and the outlet are positioned at positions on the plating surface of the substrate in azimuthally substantially opposite circumferences.

In some embodiments, the air gap between the substrate facing side of the ion resistant element and the plated surface of the substrate is measured between the plated surface of the substrate and the plane of the ion resistant element Less than about 15 mm. In certain cases, the air gap between the plated surface of the substrate and the top of the ridge may be about 0.5 to 4 mm. In certain cases, the ridges may have a height of about 2 to 10 mm. In various embodiments, the ridges are, on average, oriented substantially perpendicular to the direction of cross flow of the electrolyte. One or more or all of the ridges may have a length: width aspect ratio of at least about 3: 1. In various embodiments, the ridges are substantially coextensive with the plated surface of the substrate.

  Many different ridge shapes can be used. In some cases, ridges of at least two different shapes and / or sizes are present on the ion resistant element. The one or more ridges may include notches through which the electrolyte can flow during electroplating. The ridges may generally be shaped in the form of a rectangle, a triangle, a cylinder or a combination thereof. The ridges may have more complex shapes, e.g., generally rectangular ridges with differently shaped cutouts along the top and bottom of the ridges are contemplated. In some cases, the ridges have a triangular top. As an example, a rectangular ridge with a triangular tip can be considered. As another example, ridges having a generally triangular shape can be considered.

The ridges may extend from the channeled ion resistant plate at a right angle, or at a non-right angle, or at a combination of angles. In other words, in some embodiments, the ridges comprise a plane substantially perpendicular to the plane of the ion resistant element. Alternatively, or additionally, the ridges may include planes that are offset from the plane of the ionically resistive element by an angle that is not normal. In some embodiments, the ridges consist of two or more segments. For example, the ridges may include a first ridge segment and a second ridge segment, wherein the first and second ridge segments are each substantially equal but opposite in sign from the direction of cross flow of the electrolyte. It is offset by the opposite angle.

The ion resistant element may be configured to shape the electric field and control the nature of the electrolyte flow near the substrate during electroplating. In various embodiments, the lower manifold region may be positioned below the lower surface of the ion resistant element, the lower surface facing away from the substrate holder. The central electrolyte chamber and one or more feed channels may be configured to deliver electrolyte from the central electrolyte chamber to both the inlet and lower manifold regions. In this way, the electrolyte can be delivered directly to the inlet to initiate cross flow on the upper side of the channeled ion resistant element, and the electrolyte can be simultaneously delivered to the lower manifold region, the electrolyte being channeled It will pass through the channels of the ion resistant element and enter the void between the substrate and the channeled ion resistant element. A cross flow injection manifold may be in fluid communication with the inlet. The cross flow injection manifold may be at least partially defined by the cavity of the ion resistant element. In certain embodiments, the cross flow injection manifold is entirely within the ion resistant element.

A flow restricting ring may be positioned across the perimeter of the ion resistant element. The flow restricting ring can help redirect the flow from the cross flow injection manifold to flow in a direction parallel to the surface of the substrate. The apparatus may also include a mechanism for rotating the substrate holder during plating. In some embodiments, the inlet extends around an arc of about 90-180 degrees, around the circumference of the plated surface of the substrate. The inlet may include a plurality of azimuthally distinct inlet segments. The plurality of electrolyte feed inlets may be configured to deliver electrolyte to a plurality of azimuthally distinct inlet segments. Additionally, one or more flow control elements may be configured to independently control multiple volumetric flow rates of electrolyte in the multiple electrolyte supply inlets during electroplating. In various cases, the inlet and outlet may be adapted to create a cross flow of electrolyte within the air gap to generate or maintain shear forces on the plated surface of the substrate during electroplating. In certain embodiments, the ridges may be oriented in multiple parallel rows. The row may include two or more discrete ridges separated by non-raised air gaps, wherein the non-raised air gaps of adjacent rows are not substantially aligned with one another in the direction of the cross flow of the electrolyte.

Another aspect of the presently disclosed embodiments is an electroplating apparatus comprising: (a) including an electrolyte and an anode during electroplating of a metal on a substantially flat substrate; A chamber for electroplating; (b) a substrate holder configured to hold a substantially flat substrate such that the plated surface of the substrate is separated from the anode during electroplating; (c) ionic resistance (A) a plurality of channels adapted to transport ions through the ion resistant element during electroplating extending through the ion resistant element; (ii) plating the substrate A substrate facing side substantially parallel to the plane and separated by a void from the plating side of the substrate; and (iii) a step positioned on the substrate facing side of the ion resistant element This step has height and diameter, and The diameter is substantially coextensive with the plated surface of the substrate, and the height and diameter of the step is such that during plating the electrolyte can flow under the substrate holder, over the step and into the air gap. Sufficiently small, including steps, (d) an inlet to the cavity for introducing electrolyte into the cavity, and (e) for receiving a cross flow of electrolyte flowing within the cavity An electroplating apparatus is provided, including an outlet for the void, wherein the inlet and outlet are electrolytes within the void to create or maintain a shear force on the plated surface of the substrate during electroplating. Adapted to produce a cross flow of

  In a further aspect of the presently disclosed embodiments, a channeled ion resistant element is provided for use in an electroplating apparatus for plating materials on semiconductor wafers of standard diameter. The resistive element is: a plate having a thickness of about 2 to 25 mm, which is approximately coextensive with the plated surface of the semiconductor wafer; with at least about 1000 non-communicating through holes extending through the thickness of the plate A through hole adapted to transport ions through the plate during electroplating, and a plurality of ridges positioned on one side of the plate.

  In another aspect of the presently disclosed embodiments, a channeled ion resistant element is provided for use in an electroplating apparatus for plating materials on semiconductor wafers of standard diameter. The resistive element is: a plate having a thickness of about 2 to 25 mm, which is approximately coextensive with the plated surface of the semiconductor wafer; with at least about 1000 non-communicating through holes extending through the thickness of the plate A through hole adapted to transport ions through the plate during electroplating; and a step: the bulge of the plate in the central region of the plate; and the non-bulge of the plate positioned at the periphery of the plate Including the step, including the step.

In a further aspect disclosed herein, a method is provided for electroplating a substrate, the method comprising: (a) receiving a substantially flat substrate in a substrate holder And the substrate plating surface is exposed, and the substrate holder is configured to hold the substrate during electroplating such that the plating surface of the substrate is separated from the anode; (B) immersing the substrate in the electrolyte, forming an air gap between the plated surface of the substrate and the plane of the ion resistant element, the ion resistant element being at least about the same as the plated surface of the substrate The ion-resistant element is adapted to transport ions through the ion-resistant element during electroplating, the ion-resistant element comprising a plurality of ridges on the substrate facing side of the ion-resistant element The ridges are substantially coextensive with the plated surface of the substrate. Immersing; (c) (i) into the void from the side inlet and out of the side outlet; and (ii) void through the ion resistant element from under the ion resistant element Flowing electrolyte into contact with the substrate in the substrate holder, into and out of the side outlet, the side inlet and the side outlet being in the air gap during electroplating (D) rotating the substrate holder; and (e) flowing the electrolyte in the same manner as (c), while the electrolyte flow is designed or configured to generate the cross flow of the electrolyte; Including electroplating the material on the plated surface.

  In some embodiments, the air gap is less than about 15 mm as measured between the plated surface of the substrate and the plane of the ion resistant element. The air gap between the plated surface of the substrate and the top surface of the ridge may be about 0.5 to 4 mm. In certain implementations, the side inlets may be separated into two or more sections that are azimuthally distinct and not in fluid communication, and electrolyte flow to the azimuthally distinct sections of the inlets is independent. Can be controlled. In some cases, the flow directing element may be positioned in the air gap. The flow directing element allows the electrolyte to flow in a substantially straight flow path from the side inlet to the side outlet.

In another aspect disclosed herein, a method is provided for electroplating a substrate, the method comprising: (a) receiving a substantially flat substrate in a substrate holder And the substrate plating surface is exposed, and the substrate holder is configured to hold the substrate during electroplating such that the plating surface of the substrate is separated from the anode; (B) immersing the substrate in the electrolyte, forming an air gap between the plated surface of the substrate and the plane of the ion resistant element, the ion resistant element being at least about the same as the plated surface of the substrate The ion-resistant element is adapted to transport ions through the ion-resistant element during electroplating, the ion-resistant element comprising a step on the substrate facing side of the ion-resistant element, The step is positioned in the central region of the ion resistant element and (C) (i) from the side inlet into the air gap over the step and into the air gap, and again from the side through the outlet from the side outlet; And (ii) from under the ion-resistant element through the ion-resistant element and into the air gap to contact the substrate in the substrate holder so that it passes over the step and exits the side outlet. Flowing the electrolyte, wherein the side inlets and the side outlets are designed or configured to produce a cross flow of electrolyte in the air gap during electroplating; (d) Rotating the substrate holder; and (e) electroplating the material onto the plated surface of the substrate while flowing the electrolyte as in (c).

  These and other features are described below with reference to the associated drawings.

FIG. 1A is an isometric view of a channeled ion resistant element having a series of ridges thereon, according to a particular embodiment.

FIG. 1B is a perspective view of a substrate holding and positioning apparatus for processing semiconductor wafers electrochemically.

FIG. 1C is a partial cross-sectional view of a substrate holding assembly including a cone and a cup.

FIG. 1D is a simplified view of an electroplating cell that can be used to practice this embodiment.

FIG. 2 is an exploded view of various components of an electroplating apparatus, typically within the cathode chamber, in accordance with certain embodiments disclosed herein.

FIG. 3A is an enlarged view of the cross flow side inlet and surrounding hardware according to this particular embodiment.

FIG. 3B is an enlarged view of the cross flow outlet, CIRP manifold inlet, and surrounding hardware in accordance with various embodiments disclosed herein.

FIG. 4 is a cross-sectional view of various components of the electroplating apparatus shown in FIGS. 3A-B.

FIG. 5 shows a cross flow injection manifold and showerhead divided into six independent segments according to a specific embodiment.

FIG. 6 is a top view of the CIRP and associated hardware, with particular focus on the inflow side of the cross flow , according to one embodiment.

FIG. 7 is a simplified top view of a CIRP and associated hardware showing both the inlet and outlet sides of a cross flow manifold in accordance with various embodiments disclosed herein.

FIG. 8A illustrates a cross flow inlet region design according to a particular embodiment. FIG. 8B shows a cross flow inlet region design according to a particular embodiment.

FIG. 9 is an illustration of a cross flow inlet area showing certain relevant geometric dimensions.

FIG. 10A is a diagram of a cross flow inlet area using a channeled ion resistant plate with steps.

FIG. 10B shows an example of a channeled ion resistive plate having a step.

FIG. 11 is an illustration of a cross flow inlet region using a channeled ion resistant plate having a series of ridges.

FIG. 12 is an enlarged view of a channeled ion resistant plate having a ridge.

FIG. 13 illustrates the raised shape and design according to a particular embodiment. FIG. 14 illustrates different ridge shapes and designs from that of FIG. 13 according to certain embodiments.

FIG. 15 shows a ridge having two different types of cutouts.

FIG. 16 shows a channeled ion resistant plate having ridges of the type shown in FIG.

FIG. 17 is a simplified top view of a channeled ion resistant plate having discrete ridges separated by air gaps in a row.

FIG. 18 is an enlarged cross-sectional view of a channeled ion resistant plate having ridges.

FIG. 19 is a simplified top view of an embodiment of a channeled ion resistant plate in which the ridges are comprised of multiple segments.

FIG. 20 is experimental data showing that adding ridges on a channeled ion resistant plate can promote more uniform plating by reducing bump height and thickness variations.

  In the present application, the terms "semiconductor wafer", "wafer", "substrate", "wafer substrate" and "partially manufactured integrated circuit" are used interchangeably. It will be appreciated by those skilled in the art that the term "partially manufactured integrated circuit" can refer to a silicon wafer in the middle of any of the multiple stages of integrated circuit fabrication on a silicon wafer. In the following detailed description, the present invention will be mounted on a wafer. Semiconductor wafers typically have a diameter of 200, 300 or 450 mm. However, the present invention is not limited to the above. Workpieces may be of various shapes, sizes and materials. In addition to semiconductor wafers, other workpieces that can benefit from the present invention include various articles such as printed circuit boards.

  In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments presented herein. The embodiments disclosed herein may be practiced without some or all of these specific details. In other instances, well known process operations have not been described herein so as not to unnecessarily obscure the embodiments disclosed herein. Although the embodiments disclosed herein are described in connection with specific embodiments, it should be understood that this is not intended to limit the embodiments disclosed herein.

  In the following discussion, reference will be made to the top and bottom features (or similar terms such as upper and lower features, etc.) or elements of the embodiments disclosed herein. Here, the terms top and bottom are used merely for convenience, and represent only one framework of reference or implementation to the present invention. Other configurations are possible, such as configurations where the top and bottom components are upside down and / or configurations where the top and bottom components are left and right components or right and left components. Described herein are apparatus and methods for electroplating one or more metals on a substrate. Generally, embodiments are described where the substrate is a semiconductor wafer, but the invention is not limited thereto.

Embodiments disclosed herein include electroplating apparatus configured for control of the hydrodynamics of the electrolyte during plating to obtain a highly uniform plating layer, and methods including such control. In a specific implementation, the embodiments disclosed herein provide impinging flow (flow toward or perpendicular to the workpiece surface) and shear flow (" cross flow " or flow velocity parallel to the workpiece surface). Use a method and apparatus to generate a combination of flows).

Embodiments disclosed herein use a CIRP that provides a small channel ( cross flow manifold) between the plated surface of the wafer and the top of the channeled ion resistant plate (CIRP). While CIRP performs a number of functions, among these functions: 1) generally allows the ion current to flow from the anode located on the underside of the CIRP to the wafer; 2) upward through the CIRP, and generally fluid can flow into the wafer surface; and 3) out of the away from the transverse flow manifold region and transverse flow manifold region, it is possible to limit and restrict the flow of the electrolyte include. The flow in the cross flow manifold region consists of the fluid injected from the through holes of the CIRP, and the fluid coming in from the cross flow injection manifold located on one side of the wafer, typically on the CIRP.

  In the embodiments disclosed herein, the top surface of the CIRP is modified to improve the maximum deposition rate and plating uniformity across the entire surface of the wafer and within the plating features. The correction of the top surface of the CIRP may take the form of a step or series of ridges. FIG. 1A is an isometric view of a CIRP 150 having a series of ridges 151 thereon. These CIRP modifications are discussed in more detail below.

In certain implementations, the mechanism for applying cross flow in the cross flow manifold is, for example, an inlet having appropriate flow orientation and distribution means on or near the perimeter of the channeled ion resistant element. The inlet directs the cross flow of catholyte along the substrate facing surface of the channeled ion resistant element. The inlet is azimuthally asymmetric and is partially on the periphery of the channeled ion resistant element. The inlet may include one or more air gaps or cavities, eg, an annular cavity positioned radially outward of the channeled ion resistant element, referred to as a cross flow injection manifold. Optionally provide other elements to cooperate with the cross flow injection manifold. These other elements may include a cross flow injection flow distribution showerhead, a cross flow restriction ring, and flow directing fins, which are further described below with reference to the drawings.

  In certain embodiments, the substrate is produced to produce an average flow rate of at least about 3 cm / s (eg, at least about 5 cm / s or at least about 10 cm / s) exiting the pores of the channelized ion resistant element during electroplating. The apparatus is configured to allow the electrolyte to flow towards the plated surface of the or in a direction perpendicular to the plated surface. In certain embodiments, about 3 cm / s (eg, at least about 5 cm / s or more, at least about 10 cm / s or more, at least about 15 cm / s or more, or at least about 20 cm / s The device is configured to operate under conditions that produce an average transverse velocity of the electrolyte). In certain embodiments, these flow rates (i.e., the flow rates exiting the pores of the ion resistant element and the flow rates through the plated surface of the substrate) have a total electrolyte flow rate of about 20 L / min and the diameter of the substrate is about Suitable for electroplating cells that are 12 inches. The embodiments described herein can be practiced with various substrate sizes. In some cases, the substrate has a diameter of about 200 mm, about 300 mm or about 450 mm. Furthermore, the embodiments described herein can be implemented at a wide range of total flow rates. In particular implementations, the total flow rate of the electrolyte is about 1 to 60 L / min, about 6 to 60 L / min, about 5 to 25 L / min, or about 15 to 25 L / min. The flow rates achieved during plating may be limited by certain hardware constraints, such as the size and performance of the pump being used. It will be understood by those skilled in the art that when the technology disclosed herein is practiced with a larger pump, the flow rates listed herein may be higher.

  In some embodiments, the electroplating apparatus includes separate anode and cathode chambers, wherein different electrolyte configurations, electrolyte circulation loops, and / or fluid dynamics exist in each of the two chambers. An ion permeable membrane may be used to prevent direct convective transport (transfer of material by flow) of one or more components between the chambers, and to maintain a desired separation between the chambers. This membrane can inhibit a large amount of electrolyte flow, and specific species such as organic additives while selectively permeating and transporting ions, such as cations only (cation exchange membranes) or anions only (anion exchange membranes) Transport can be eliminated. As a specific example, in some embodiments, the membrane comprises NAFION®, a cation exchange membrane from DuPont (Wilmington, DE) or related ion selective polymers. In other cases, the membrane does not contain ion exchange material, but instead contains microporous material. Conventionally, the electrolyte in the cathode chamber is referred to as "catholyte" and the electrolyte in the anode chamber is referred to as "anolyte". The anolyte and catholyte often have different compositions and the anolyte contains little or no plating additive (eg, accelerator, inhibitor and / or leveling agent) and the catholyte contains Additives are included at significant concentrations. The concentrations of metal ions and acids may also differ between the two chambers. An example of an electroplating apparatus that includes a separated anode chamber is described in U.S. Patent No. 6,527,920 filed on November 3, 2000 (Attorney Docket No. NOVLP 007), U.S. Patent No. 6,821,407, filed August 27, 2002. No. (Attorney Docket No. NOVLP 048), US Pat. No. 8,262,871 filed on Dec. 17, 2009 (Attorney Docket No. NOVLP 308), each of which is incorporated herein by reference in its entirety. It is incorporated.

  In some embodiments, the membrane need not include an ion exchange material. In some embodiments, the membrane is made of a microporous material such as polyethersulfone manufactured by Koch Membrane (Wilmington, Mass.). Films of this type are most suitable for applications using inert anodes such as tin-silver plating and gold plating, but may also be used for applications using soluble anodes such as nickel plating.

In certain embodiments, the catholyte may flow into the electroplating cell through one of two main paths, as described more fully elsewhere herein. In the first pass, the catholyte is supplied to the manifold area, which is then placed under the CIRP and usually (but not necessarily) on the cell membrane and / or membrane frame holder. It is called "CIRP manifold area". From the CIRP manifold area, the catholyte travels upward through the various pores of the CIRP and into the CIRP into the substrate void (sometimes referred to as cross flow or cross flow manifold area) to the wafer surface. Move in the direction to head. In the second crossflow electrolyte supply passage, catholyte from one side of the cross-flow injection manifold region is supplied to the cross-flow injection manifold region. From the cross flow injection manifold, the catholyte passes through the CIRP and travels to the void of the substrate (ie, the cross flow manifold), flowing across the surface of the substrate in a direction generally parallel to the surface of the substrate.

  Although some aspects described herein can be used with various types of plating apparatus, for the sake of simplicity and clarity, most of the examples are "wafer-type" plating apparatus with the wafer face down. Shall be concerned with In such devices, the workpieces to be plated (typically the semiconductor wafer in the above example) are generally oriented substantially horizontally (in some cases, throughout part or all of the plating process) It may be powered during the plating to obtain a generally vertically upward electrolyte convection pattern, which may change from perfect horizontal by only a few degrees. Integration of impinging flow from the center of the wafer to the edge, and the nature of the increased angular velocity of the edge relative to the center of the rotating wafer, produces a radially increasing shear (parallel to the wafer) flow rate . One example of a fountain-type plating cell / device member is Novellus Systems, Inc. A Saber (R) electroplating system manufactured and marketed by San Jose, CA. In addition, fountain-type electroplating systems are disclosed, for example, in US Pat. No. 6,800,187 filed on Aug. 10, 2001 (Attorney Docket No. NOVLP 020) and US Pat. No. 8,308,931 filed on Nov. 7, 2008. Attorney Docket No. NOVLP 299), which are incorporated herein by reference in their entirety.

  The substrate to be plated is generally flat or substantially flat. Here, substrates having features such as trenches, vias, photoresist patterns, etc. are considered substantially flat. These features are often, but not necessarily, on a microscopic scale. In many embodiments, one or more portions of the substrate surface may be masked against exposure to the electrolyte.

  The following description of FIG. 1B provides general and non-limiting content that aids in the understanding of the devices and methods described herein. FIG. 1B is a perspective view of a wafer holding and positioning apparatus 100 for processing semiconductor wafers electrochemically. The apparatus 100 includes wafer engaging components (sometimes referred to herein as "clamshell" components). The actual clamshell includes a cup 102 and a cone 103 that can apply pressure between the wafer and the encapsulant, whereby the wafer is secured within the cup.

  The cup 102 is supported by a column 104 connected to the top plate 105. The assemblies (102-105) are combined into an assembly 101, which is driven by a motor 107 through a mandrel 106. The motor 107 is attached to the mounting bracket 109. The mandrel 106 transmits torque to the wafer (not shown in this view), which allows the wafer to rotate during plating. A pneumatic cylinder (not shown) in the stem 106 also provides a vertical force between the cup and the cone 103, thereby between the wafer stored in the cup and the sealing member (lip seal). Generate a seal. For the purposes of this discussion, the assembly containing parts 102-109 will be collectively referred to as wafer holder 111. However, the concept "wafer holder" generally extends to various combinations and subcombinations of parts that engage the wafer to allow movement and positioning of the wafer.

  A tilting assembly including a first plate 115 slidably connected to a second plate 117 is connected to the mounting bracket 109. Drive cylinders 113 are connected to both plates 115 and 117 at axle joints 119 and 121, respectively. Thus, the drive cylinder 113 provides a force to slide the plate 115 (and hence the wafer holder 111) across the plate 117. The distal end of wafer holder 111 (i.e. mounting bracket 109) moves along an arcuate path (not shown) which defines the contact area between plate 115 and plate 117 and thus the proximal end of wafer holder 111 (i.e. The cup and cone assembly) tilts on a virtual pivot. This allows the wafer to be angled into the plating bath.

  The entire apparatus 100 is vertically lifted up and down to immerse the proximal end of the wafer holder 111 in a plating solution through another actuator (not shown). Thus, the two-part positioning mechanism provides vertical movement along a trajectory perpendicular to the electrolyte and tilting movement that can deflect the horizontal orientation of the wafer (parallel to the electrolyte surface) (Angled wafer immersion performance ). A more detailed description of mobility performance and associated device 100 hardware can be found in US Pat. No. 6,551,487 (Attorney Docket No. NOVLP 022), filed May 31, 2001 and issued April 22, 2003. Which is incorporated herein by reference in its entirety.

  It should be noted that the apparatus 100 is typically used with a particular plating cell having an anode (eg, a copper anode or a non-metal inert anode) and a plating chamber containing an electrolyte. The plating cell may also include piping or piping connections to circulate the electrolyte throughout the plating cell and to the workpiece being plated. The plating cell may also include a membrane or other separator designed to maintain different chemical composition of the electrolyte in the anode and cathode compartments. Also optionally, means may be provided to move the anolyte to the catholyte reservoir or main plating reservoir by physical means (e.g. direct transport with a pump including a valve or overflow trough).

  The clamshell cup and cone assembly is described in more detail below. FIG. 1C is a cross-sectional view of portion 101 including cone 103 and cup 102 of assembly 100. Note that this figure is not intended to accurately illustrate the cup and cone product assembly, but is a stylized figure for discussion purposes. The cup 102 is supported by the top plate 105 via a support 104, and the support is attached by a screw 108. In general, cup 102 provides a support on which wafer 145 is mounted. This includes an opening through which the electrolyte from the plating cell can contact the wafer. The wafer 145 has a front side 142, and the front side 142 is plated. The circumference of the wafer 145 is placed on the cup 102. The cone 103 applies pressure to the backside of the wafer to hold the wafer in place during plating.

  To load the wafer into the assembly 101, the mandrel 106 lifts the cone 103 from the illustrated position until the cone 103 contacts the top plate 105. From this position, an air gap is created between the cup and the cone that allows the wafer 145 to be inserted, thereby allowing the wafer 145 to be loaded into the cup. Next, the cone 103 is lowered and the wafer engages against the circumference of the cup 102 as shown, and a series of electrical contacts (not shown in FIG. 1C) radially across the lip seal 143 along the wafer's periphery Match with). In embodiments using a step or series of ridges on a channeled ion resistant plate (CIRP), the wafer may be inserted in a slightly different manner to avoid contact of the wafer or wafer holder with the CIRP. In this case, the wafer holder may first insert the wafer at an angle to the surface of the electrolyte. The wafer holder may then rotate the wafer such that the wafer is in a horizontal position. While the wafer is rotating, the wafer may continue to move downward into the electrolyte as long as the CIRP is not impeded. The final portion of the wafer insertion may include inserting the wafer straight down. This straight down movement can be performed when the wafer is oriented horizontally (i.e. after the wafer is in a non-tilted state).

  Mandrel 106 transmits both the vertical force to engage cone 103 to wafer 145 and the torque to rotate assembly 101. These transmitted forces are indicated by arrows in FIG. 1C. Note that plating of the wafer is typically performed during the rotation of the wafer (as shown by the dashed arrow at the top of FIG. 1C).

  The cup 102 has a compressible lip seal 143 which, when engaged with the wafer 145, forms a fluid tight seal. The vertical forces from the cone and the wafer compress the lip seal 143 thereby forming a fluid tight seal. The lip seal prevents the electrolyte from contacting the back side of the wafer 145 (here, contaminating species such as copper or tin ions may be introduced directly into the silicon) and contacting fragile parts of the device 101. An encapsulant placed at the cup-wafer interface may be provided (not shown) to form a fluid tight seal to further protect the backside of the wafer 145.

  Cone 103 also includes encapsulant 149. As shown, the seal 149 is located near the edge of the cone 103 and, when engaged, is located in the upper region of the cup. This again protects the backside of wafer 145 from any electrolyte that may enter the clamshell from above the cup. The encapsulant 149 may be secured to a cone or cup and may be a single encapsulant or a plurality of components.

  Once plating is initiated, the cone 103 is lifted onto the cup 102 and the wafer 145 is introduced into the assembly 101. Typically, the front side 142 of the wafer is lightly placed on the lip seal 143 as the robot arm initially introduces the wafer into the cup 102. During plating, the assembly 101 is rotated to help achieve uniform plating. In subsequent figures, assembly 101 is more simplified and shown in conjunction with components for controlling the hydrodynamics of the electrolyte at the plating surface 142 of the wafer during plating.

  FIG. 1D is a cross-sectional view of a plating apparatus 725 for plating metal on a wafer 145, which is held, positioned, and rotated by the wafer holder 101. Apparatus 725 includes a plating cell 155, which is a dual chamber cell having an anode chamber 160, eg, a copper anode, and an anode solution. The anode and cathode chambers are separated by, for example, a cationic membrane 740 supported by a support member 735. The plating apparatus 725 includes the CIRP 410 as described above. The flow switching valve 325 is at the top of the CIRP 410, which assists in the generation of transverse shear flow as described above. The catholyte is introduced into the cathode chamber (above the membrane 740) via the flow port 710. From flow port 710, the catholyte passes through CIRP 410 as described above, creating an impinging flow on the plated surface of wafer 145. In addition to the catholyte flow port 710, the additional flow port 710a introduces catholyte at its outlet remote from the air gap / outlet of the flow diverter valve 325. In this embodiment, the outlet of flow port 710 a is formed as a channel of flow shaping plate 410. The resulting function is to enhance cathodic flow across the wafer surface and standardize the catholyte flow to plate the CIRP 410 and wafer to standardize the flow vector across the wafer 145 (and the flow shaping plate 410). Directly into the plating area formed between it and the surface 145.

A number of figures are provided to further illustrate and explain the embodiments described herein. These figures among others include various views of the structural elements and flow paths associated with the electroplating apparatus disclosed herein. These elements are given specific names / reference numbers, which are used consistently in the description with respect to FIGS. FIG. 2 includes a wafer holder 254, a cross flow limiting ring 210, a cross flow ring gasket 238, a channeled ion resistant plate (CIRP) 206 with a cross flow shower head 242, and a membrane frame 274 with a fluid conditioning rod 270. 1 shows a plurality of elements present in the embodiment of. In FIG. 2 these elements are shown in an exploded view to illustrate how these parts fit.

  Most of the following embodiments assume that the electroplating apparatus includes a separate anode chamber. The features described herein are included in the cathode chamber. With reference to FIGS. 3A, 3B and 4, the bottom of the cathode chamber is the membrane frame 274 and the membrane 202 (note: the membrane 202 is extremely thin and thus not actually removed, but as being located on the lower surface of the membrane frame 274). Position 202), which separate the anode chamber from the cathode chamber. Any number of possible anode and anode chamber configurations may be used.

In the following description, the control of the catholyte in the cross flow manifold or manifold region 226 is largely focused. This cross flow manifold region 226 may also be referred to as the air gap or the CIRP-to-wafer air gap 226. The catholyte enters the cross flow manifold 226 through (1) the channels of the channeled ion resistant plate 206 and (2) two separate inlet points of the cross flow initiation structure 250. The catholyte reaching the cross flow manifold 226 through the channels of the CIRP 206 is typically oriented substantially vertically towards the surface of the workpiece. The catholyte delivered in this manner by the channels can form a small jet stream that impinges on the surface of the workpiece, which is typically slow (eg, about 1 to 30 rpm) relative to the channeled plate 206. ) Is rotating. In contrast, the catholyte reaching the cross flow manifold 226 via the cross flow initiation structure 260 is oriented substantially parallel to the plane of the workpiece.

  As indicated in the above discussion, the channeled ion resistive plate 206 (also referred to as a channeled ion resistive element, CIRP, a high resistivity virtual anode or HRVA) is a working electrode (wafer or plate) during plating. Positioned between the substrate) and the counter electrode (anode), thereby providing large local ion system resistance (and thereby controlling and shaping the electric field) relatively near the wafer boundary, and electrolyte flow Control the nature of The various figures of the present application show the relative position of the channeled ion resistant plate 206 with respect to other structural features of the devices disclosed herein. An example of such an ion resistant element 206 is described in US Pat. No. 8,308,931 filed on Nov. 7, 2008 (Attorney Docket No. NOVLP 299), which has already been incorporated by reference in its entirety. Is incorporated into the book. The channeled ion resistant plates described in this document improve radial plating uniformity on wafer surfaces such as those with relatively low conductivity or those with very thin resistive seed layers. It is appropriate for In many embodiments, the channeled ion resistant plate is adapted to include a step or series of ridges as described above and further described below.

A “membrane frame” 274 (sometimes referred to in other documents as an anode membrane frame) is a structural element used to support the membrane 202 which separates the anode chamber from the cathode chamber in some embodiments. The membrane frame 274 may have other features with respect to the particular embodiments disclosed herein. In particular, with respect to the illustrated embodiment, the membrane frame 274 may include flow channels 258 and 262 for delivering catholyte to the CIRP manifold 208 or to the cross flow manifold 226. Further, the film frame 274 may include a showerhead plate 242 configured to deliver catholyte cross flow to the transverse flow manifold 226. Membrane frame 274 may also include cell retaining wall 282, which is useful in determining and adjusting the top level of the catholyte. Various figures of the present application show the membrane frame 274 in the context of other structural features associated with the cross flow device disclosed herein.

Membrane frame 274 is a rigid structural member for holding membrane 202, which is typically an ion exchange membrane that serves to separate the anode chamber from the cathode chamber. As described, the anode chamber may include an electrolyte of a first composition, while the cathode chamber includes an electrolyte of a second composition. Membrane frame 274 may also include a plurality of fluid conditioning rods 270 (sometimes referred to as flow restriction elements) that can be used to help control the delivery of fluid to channeled ion resistant element 206. Membrane frame 274 defines the bottom of the cathode chamber and the top of the anode chamber. All of the components described herein are located on the anode chamber and on the workpiece side of the electrochemically plated cell above the anode chamber membrane 202. These can all be considered as part of the cathode chamber. However, it should be understood that the particular implementation of the cross flow injection device does not use a separate anode chamber, and thus the membrane frame 274 is not required.

A channeled ion resistant plate 206 and a cross flow ring gasket 238 and a cross flow restriction ring 210 of the wafer are generally disposed between the workpiece and the membrane frame 274, the cross flow ring gasket 238 and the cross flow restriction ring of the wafer. Each 210 may be fixed to a channeled ion resistant plate 206. More specifically, the cross flow ring gasket 238 may be positioned directly on the CIRP 206 and the cross flow limiting ring 210 of the wafer may be positioned to cover the cross flow ring gasket 238 and the channeled ion resistant plate 206 It may be fixed to the upper surface of the, effectively sandwiching the gasket 238. Various views of the present application show the cross flow restriction ring 210 disposed relative to the channeled ion resistant plate 206. Additionally, CIRP 206 may include a step or series of ridges, as described further below.

  The top associated structural feature of the present disclosure, as shown in FIG. 2, is a workpiece or wafer holder. In certain embodiments, the workpiece holder may be a cup 254, which typically has a cone and cup, such as the design implemented in the above-described Saber® electroplating jig from Lam Research Corporation. Used in clamshell type designs with For example, FIGS. 2, 8A and 8B show the relative orientation of the cup 254 with respect to the other elements of the device.

Figure 3A is an enlarged sectional view of the transverse flow inlet side of the electroplating apparatus according to embodiments described herein. FIG. 3B is an enlarged cross-sectional view of the cross flow outlet side of the electroplating apparatus according to embodiments described herein. FIG. 4 is a cross-sectional view showing both the inlet and outlet sides of the plating apparatus according to certain embodiments described herein. During the plating process, the catholyte fills and occupies the area between the top of the membrane 202 on the membrane frame 274 and the membrane frame stop wall 282. This catholyte area is divided into three sub-areas: 1) Cationic membrane 202 (this element corresponds to the lower manifold area 208) under the CIRP 206 and separated (in the design using an anodic chamber's cationic membrane) above the also) be referred to, channeled ions resistive plate manifold region 208; 2) between the upper surface of the wafer and CIRP206, transverse flow manifold region 226; outside and in, and 3) clamshell / cup 254 It can be divided into a cell upper area or "electrolyte sealing area" that is inside the cell blocking wall 282 (sometimes referred to as the physical portion of the membrane frame 274). If the wafer is not immersed and the clamshell / cup 254 is not in the down position, the second and third regions combine to a single region.

  FIG. 3B is a cross-sectional view of a single inflow port feeding the CIRP manifold 208 through the channel 262. The dotted lines indicate the flow of fluid.

The catholyte can be delivered to the electroplating cell at a central catholyte inlet manifold (not shown), which may be located at the base of the cell and supplied in a single pipe. From here, the catholyte may be divided into two different channels or streams. One stream (eg, six of the twelve feed holes) flows the catholyte through channel 262 to the CIRP manifold region 208. After the catholyte is delivered to the CIRP manifold 208, it flows up the microchannels of the CIRP and flows to the cross flow manifold 226. The other stream (eg, the other six feed holes) flows the catholyte to the cross flow injection manifold 222. The electrolyte now passes through the distribution holes 246 (which may be greater than about 100 in certain embodiments) of the cross flow shower head 242. After passing through the cross flow showerhead holes 246, the flow direction of the catholyte changes from (a) perpendicular to the wafer to (b) parallel to the wafer. Such a change in flow direction occurs because the flow impinges on and is limited by the surface of the inlet cavity 250 of the cross flow restricting ring 210. Finally, the two catholyte streams first separated in the central catholyte inlet manifold at the base of the cell recombine as they enter the cross flow manifold region 226.

In the embodiment shown in FIGS. 3A, 3 B and 4, a portion of the catholyte entering the cathode chamber is supplied directly to the channelized ion resistant plate manifold 208 and a portion is supplied directly to the cross flow injection manifold 222. At least a portion (possibly all) of the catholyte delivered to the channeled ion resistant plate manifold 208 passes through the various microchannels of the plate 206 to reach the cross flow manifold 226. Catholyte entering the cross-flow manifold 226 through the channels of the channeled ions resistant plate 206 is a substantially into the crossflow manifold as the vertical direction of the jet stream (in some embodiments, an angle with the channel Made to have, and thus the channels are not completely perpendicular to the surface of the wafer, eg, the jet flow angle may be up to about 45 ° to the angle perpendicular to the wafer surface). The portion of the catholyte that enters crossflow injection manifold 222 is delivered directly to crossflow manifold 226, where this catholyte enters crossflow manifold 226 as the horizontally oriented crossflow below the wafer. . Catholyte transverse flow of, on the assumption that flow to the transverse flow manifold 226, the across-flow injection manifold 222 and transverse flow showerhead plate 242 (a specific embodiment, has a diameter of about 0.048 inches, about 139 pieces of variance Flow through the hole 246 and subsequently re-directed from the vertically upward flow to a flow parallel to the wafer surface by the action / geometrical dimension of the inlet cavity 250 of the cross flow restriction ring 210 .

The absolute angles of the cross flow and jet flow need not be exactly horizontal or exactly vertical, or even need to be exactly oriented at 90 ° to each other. Generally, however, the transverse flow of the catholyte in the transverse flow manifold 226 is along a generally in the direction of the workpiece surface, the direction of the catholyte jet stream emitted from the top surface of the micro channel with the ion-resistant plate 206 Flow generally towards / perpendicular to workpiece surface. Such mixing of the cross flow and the impinging flow at the wafer surface helps to promote the achievement of more uniform plating results. In certain embodiments, ridges are used to help disperse the cross flow of the electrolyte, whereby the cross flow is reoriented in the direction towards the wafer surface.

As described above, the catholyte entering the cathode chamber (i) flows from the channeled ion resistive plate manifold 208 through the channels of the CIRP 206 to the cross flow manifold 226; (ii) the cross flow injection manifold 222 And then divided into catholyte flowing through the holes 246 of the showerhead 242 to the cross flow manifold 226. Flow directly into the crossflow injection manifold region 222 may be through the inlet port of the crossflow limiting ring (sometimes referred to as the crossflow side inlet 250), parallel to the wafer, one side of the cell Released from In contrast, jets of fluid entering the cross flow manifold region 226 through the microchannels of the CIRP 206 enter from the lower side of the wafer and from the lower side of the cross flow manifold 226, and the jet flow fluid is deflected within the cross flow manifold 226. (Reoriented) and flows parallel to the wafer to the outlet port 234 (sometimes referred to as the cross flow outlet or outlet) of the cross flow limiting ring.

In a specific embodiment, six separate supply channels 258 are present to deliver catholyte directly to the crossflow injection manifold 222 (which is then delivered to the crossflow manifold 226). In order to generate a transverse flow in the cross-flow manifold 226, outlet of these channels 258 is towards the azimuthal non-uniform manner across-flow manifold 226. Specifically, they enter the cross flow manifold 226 on a particular side or azimuthal area (eg, the inlet side) of the cross flow manifold 226.

In the particular embodiment shown in FIG. 3A, the fluid path 258 for delivery of cathode fluid directly into crossflow injection manifold 222 includes four separate elements prior to reaching the cross-flow injection manifold 222: (1) (2) dedicated channels of the membrane frame 274; (3) dedicated channels of the ion resistant element 206 with channels (these dedicated channels cross flow from the CIRP manifold 208 ) And (4) pass through the fluid path of the cross flow restriction ring 210 of the wafer (different from the one-dimensional microchannels used to deliver catholyte to the manifold 226); If the elements are of different configurations, the cathode may not flow through each of these separate elements.

As noted above, the portion of the flow path that passes through the membrane frame 274 and is supplied to the cross flow injection manifold 222 is referred to as the cross flow supply channel 258 of the membrane frame. Similarly, the portion of the flow path that passes through the membrane frame 274 and is supplied to the CIRP manifold is called the cross flow supply channel 262 supplied to the channeled ion resistant plate manifold 208 or the CIRP manifold supply channel 262 . In other words, the term “ crossflow feed channel” includes both the catholyte feed channel 258 feeding the crossflow injection manifold 222 and the catholyte feed channel 262 feeding the CIRP manifold 208. One difference between these flows 258 and 262 is that, as described above, the direction of flow through CIRP 206 is initially oriented towards the wafer and then parallel to the wafer due to the presence of cross flow in the wafer and the cross flow manifold. While varying, a portion of the crossflow coming from the crossflow injection manifold 222 and exiting from the inlet port 250 of the crossflow limiting ring is substantially parallel to the wafer in the crossflow manifold. It is to start. While not wishing to be encompassed by any particular norm or theory, such combination and mixing of impinging flow and parallel flow greatly enhance the penetration of the flow into the concave / embedded features. It is thought to help improve and thereby improve mass transport. Such mixing can be further enhanced if the CIRP surface includes a series of ridges. By creating a spatially uniform convection field under the wafer and rotating the wafer, each feature and each die exhibit substantially the same flow pattern throughout the rotation and plating process.

The flow path for delivering the cross flow of electrolyte is started vertically upward to pass the cross flow supply channel 258 of the plate 206. Subsequently, this flow path enters the cross flow injection manifold 222 formed in the body of the channeled ion resistant plate 206. Across-flow injection manifold 222 may distribute the various independent fluid from the supply channel 258 (e.g., from each of the six independent transverse flow feed channels) into the crossflow variety plurality of flow distribution holes 246 of the shower head plate 242, the plate An azimuthally arranged cavity which may be a shunt channel within 206. The cross flow injection manifold 222 is disposed along an angular portion of the peripheral or edge area of the channeled ion resistant plate 206. See, for example, FIGS. 3A and 4-6. Figures 3A and 4 have already been described. FIG. 5 shows the showerhead plate 242 positioned across the cross flow injection manifold 222. FIG. 6 similarly shows the showerhead plate 242 across the crossflow injection manifold 222 in conjunction with various other elements of the plating apparatus.

In particular embodiments, the cross flow injection manifold 222 forms a C-shaped structure that spans an angle of about 90 to 180 degrees of the circumferential area of the plate, as shown in FIGS. In a particular embodiment, the angular range of the cross flow injection manifold 222 is about 120-170 °, and in a more specific embodiment, about 140-150 °. In these or other embodiments, the angular range of the cross flow injection manifold 222 is at least about 90 °. In many implementations, the showerhead 242 is over approximately the same angular range as the cross flow injection manifold 222. In addition, the total inlet structure 250 (which often includes one or more of the cross flow injection manifold 222, the shower head plate 242, the shower head aperture 246, and the opening of the cross flow restriction ring 210) , May be present over the same angular range as described above.

In some embodiments, the cross flow in the injection manifold 222 forms a continuous fluid communication cavity in the channeled ion resistive plate 206. In this case, all of the outlet cross flow supply channel 258 supplies the cross-flow injection manifold is moving towards one continuous and connected across-flow injection manifold chamber. In other embodiments, the cross flow injection manifold 222 and / or the cross flow showerhead 242 may have two or more different angles and fully or partially as shown in FIG. 5 (showing six separate segments). Divided into separate segments. In some embodiments, the number of angularly separated segments is about 1 to 12 or about 4 to 6. In a specific embodiment, each of these angularly distinct segments is in fluid communication with a separate cross flow supply channel 258 disposed in the channeled ion resistant plate 206. Thus, for example, there may be six angularly separated discrete sub-regions within the cross flow injection manifold 222, each of which is supplied by the separated cross flow feed channel 258. In particular embodiments, these separate sub-regions of the cross-flow injection manifold 222 each have the same volume and / or the same angular range.

In most cases, the catholyte exits the cross flow injection manifold 222 and passes through a cross flow showerhead plate 242 having a plurality of angularly separated catholyte outlet ports (holes) 246. See, for example, FIGS. 2, 3A and 6 (the catholyte outlet / hole 246 not shown in all figures). In particular embodiments, as shown, for example, in FIG. 6, the cross flow showerhead plate 242 is integrated with the channeled ion resistant plate 206. In some embodiments, the showerhead plate 242 is glued, bolted or otherwise secured to the top of the cross flow injection manifold 222 of the channeled ion resistant plate 206. In certain embodiments, the upper surface of the cross flow shower head 242 is coplanar with the plane or upper surface of the channeled ion resistant plate 206 (except for any steps or bumps on the CIRP 206), or Slightly lifted. In this way, the catholyte flowing through the crossflow injection manifold 222 is first directed vertically upward through the holes 246 in the showerhead and then laterally to the crossflow manifold 226 under the crossflow limiting ring 210. Moving, this causes the catholyte to enter the cross flow manifold 226 in a direction substantially parallel to the surface of the wafer. In other embodiments, the showerhead 242 may be oriented such that the catholyte exiting the holes 246 of the showerhead is already moving in a direction parallel to the wafer.

In a specific embodiment, the cross flow showerhead 242 has about 140 angularly separated catholyte outlet holes 246. More generally, any number of holes may be used that properly establish uniform cross flow in cross flow manifold 226. In particular embodiments, the cross flow shower head 242 has about 50-300 such catholyte outlet holes 246. In certain embodiments, such holes are about 100-200. In certain embodiments, such holes are about 120-160. In general, the size of the independent port or hole 246 is approximately 0.020 to 0.1. It may be in the range of inches, and more specifically about 0.03 to 0.06 inches in diameter.

In certain embodiments, these holes 246 are angularly uniformly distributed along the full angular range of the cross flow shower head 242 (ie, the spacing between the holes 246 is two adjacent to the cell center Determined by the fixed angle between the holes). In another embodiment, the holes 246 are angularly non-uniformly distributed along this angular range. In certain embodiments, the angularly non-uniform distribution of holes is nevertheless a linear ("x-direction") uniform distribution. In other words, in the latter example, the distribution of the holes is such that, when projected onto an axis perpendicular to the direction of the cross flow (this axis is the "x" direction), the holes are equally spaced apart. Distribution. Each hole 246 is positioned at the same radial distance from the cell center and is spaced the same distance in the "x" direction from adjacent holes. The net effect of having these angularly non-uniform holes 246 is that the overall cross flow pattern is substantially uniform. In contrast, if the holes are angularly uniformly spaced, the edge region of the substrate has more holes than needed for uniform cross flow , so the cross flow across the center of the substrate is: It is lower than the cross flow over the edge area.

In certain embodiments, the direction of catholyte exiting the cross flow showerhead 242 is further controlled by the cross flow restriction ring 210 of the wafer. In certain embodiments, the ring 210 extends around the entire perimeter of the channeled ion resistant plate 206. In a particular embodiment, the cross-section of the cross flow restriction ring 210 is L-shaped as shown in FIGS. 3A, 3B and 4. This shape may be chosen to fit the bottom of the holder / cup 254 of the substrate. In certain embodiments, the wafer cross flow restriction ring 210 includes a series of flow directing elements, such as directional fins 266, in fluid communication with the outlet holes 246 of the cross flow shower head 242. This fin 266 is clearly shown in FIG. 7 but can also be seen in FIGS. 3A and 4. Directional fins 266 define generally separated fluid passages below the upper surface of the cross flow restriction ring 210 of the wafer and between adjacent directional fins 266. In some cases, the purpose of the fins 266 is to move the flow out of the borehole 246 of the crossflow showerhead from the radially inward direction to the "left to right" trajectory (left is the crossflow inlet) Re-orientation and restriction to flow through side 250, and right is through inlet side 234). This helps to establish a substantially linear cross flow pattern. The catholyte exiting the holes 246 of the cross flow shower head 242 is directed by the directional fins 266 along the streamlines created by the orientation of the directional fins 266. In certain embodiments, all directional fins 266 of the cross flow restriction ring 210 of the wafer are parallel to one another. This parallel arrangement helps to establish a uniform cross flow direction in the cross flow manifold 226. In various embodiments, the directional fins 266 of the cross flow restriction ring 210 of the wafer are disposed along both the inlet 250 side and the outlet 234 side of the cross flow manifold 226. In other cases, the fins 266 may be disposed only along the inlet region 250 of the cross flow manifold 226.

As indicated above, the catholyte flowing in the cross flow manifold 226 passes from the inflow region 250 of the cross flow restriction ring 210 of the wafer to the outlet side 234 of the ring 210, as shown in FIGS. 3B and 4. Do. In certain embodiments, there are a plurality of directional fins 266 on the outlet side 234 that may be parallel to and aligned with the directional fins 266 on the inlet side. Transverse flow through a channel direction fins 266 has generated the outlet side 234, leaving the subsequent crossflow manifold 226. This flow is then flowed to another region of the cathode chamber, generally radially outward, past the wafer holder 254 and the cross flow control ring 210, and fluid is collected by the upper stop wall 282 of the membrane frame and temporarily And then flow over the retaining wall 282 for storage and retention. Thus, it should be understood that the figures (e.g. 3A, 3B and 4) show only a partial path of the overall catholyte circulation path into and out of the cross flow manifold. Note, for example, in the embodiments shown in FIGS. 3 b and 4, the fluid exiting the cross flow manifold 226 does not pass through the small holes or return through the same channels as the inlet side feed channel 258, and the accumulation described above It flows outward in a direction generally parallel to the wafer so as to be integrated in the area.

Returning to the embodiment of FIG. 6, a top view is shown here looking down the cross flow manifold 226. This figure shows the location of the cross flow injection manifold 222 embedded in the channelized ion resistant plate 206 along the showerhead 242. Although the outlet holes 246 on the shower head 242 are not shown, it is understood that such outlet holes are present. Also shown is a fluid conditioning rod 270 for the flow of the cross flow injection manifold. Although the cross flow limiting ring 210 is not shown in this figure, the outer shape of the sealing gasket 238 of the cross flow limiting ring, which seals between the cross flow limiting ring 210 and the upper surface of the CIRP 206, is shown. . Other elements shown in FIG. 6 include cross flow restriction ring fixtures 218, membrane frame 274, and screw holes 278 on the anode side of CIRP 206 (which can be used, for example, for insertion of a cathode shield).

In some embodiments, the geometric dimensions of the outlet 234 of the cross flow limiting ring may be adjusted to further optimize the cross flow pattern. For example, if the cross flow pattern branches to the edge of the limiting ring 210, this may be corrected by reducing the open area of the outer area of the outlet 234 of the cross flow limiting ring. In certain embodiments, the outlet manifold 234 may include separate sections or ports, similar to the cross flow injection manifold 222. In some embodiments, the number of outlet sections is about 1 to 12, or about 4 to 6. The ports are azimuthally separated and take different (usually adjacent) locations along the outlet manifold 234. In some cases, the relative flow through each port can be controlled independently. This control may be achieved, for example, using a control rod 270 similar to the control rod described above for inlet flow. In another embodiment, the flow through different sections of the outlet can be controlled by the geometry of the outlet manifold. For example, an outlet manifold with a small open area near each side edge and a large open area near the center, a solution flow that has more flow near the center of the flow outlet and less flow near the outlet Pattern is born. Other methods of controlling the relative flow through the ports of outlet manifold 234 (eg, pumps, process control valves, etc.) may be used as well.

As described above, catholyte entering the catholyte chamber is separately oriented through the plurality of channels 258 and 262 into the cross flow injection manifold 222 and the channelized ion resistant plate manifold 208. In certain embodiments, the flow through these independent channels 258 and 262 is controlled independently of one another by appropriate mechanisms. In some embodiments, the mechanism comprises a separate pump for delivering fluid to an independent channel. In other embodiments, a single pump may be used to supply the main catholyte manifold and may include various flow restricting elements adjustable to one or more of the channels, thereby providing a plurality of channels 258 and The relative flow is adjusted between 262 and between the cross flow injection manifold 222 and the CIRP manifold 208 region and / or along the circumference of the cell. In the various embodiments illustrated, one or more fluid conditioning rods 270 (sometimes referred to as flow control elements) are placed in the channels to provide independent control. In the illustrated embodiment, the fluid conditioning rod 270 provides an annular space that restricts the flow of catholyte into the cross flow injection manifold 222 or the channelized ion resistant plate manifold 208. The fluid conditioning rod 270 essentially produces no resistance to flow in the fully contracted state. In the fully engaged state, the fluid conditioning rod 270 generates maximum resistance to flow and, in some implementations, stops all flow through the channel. In the intermediate state or position, the rod 270 enables intermediate level flow control as fluid flows through the restricted annular space between the inner diameter of the channel and the outer diameter of the fluid adjustment rod.

In some embodiments, adjustment of the fluid conditioning rod 270 allows the electroplating cell operator or pilot to favor flow to the cross flow injection manifold 222 or the channelized ion resistant plate manifold 208. it can. In certain embodiments, independent adjustment of the fluid conditioning rod 270 of the channel 258 delivering the catholyte directly to the cross flow injection manifold 222 allows the operator or operator to orientate the flow of fluid to the cross flow manifold 226. It can control the component (azimuthal component).

8A-B are cross-sectional views of the cross flow inlet manifold 222 and the corresponding cross flow inlet 250 for the plating cup 254. The position of the cross flow inlet 250 is at least partially defined by the position of the cross flow restriction ring 210. In particular, the inlet 250 may be considered as beginning at the end of the cross flow restriction ring 210. In FIG. 8A, the end point of the limiting ring 210 (and the start point of the inlet 250) is below the edge of the wafer, while in FIG. 8B, the end / start point is compared to the design of FIG. 8A. Below the plating cup and further radially outward of the edge of the wafer. Also, the cross flow injection manifold 222 of FIG. 8A has a step in the cross flow ring cavity (where the generally left-pointing arrow begins to rise upward), which is the point of fluid inflow to the cross flow manifold region 226. Turbulence can form in the vicinity. In certain cases, fluid trajectory bulging near the edge of the wafer by providing some distance (eg, about 10-15 mm) to make the solution flow more even before flowing across the wafer surface. It may be beneficial to allow the plating solution to move from the cross flow injection manifold area 222 and enter the cross flow manifold area 226.

FIG. 9 is an enlarged view of the inlet of the plating apparatus. This figure is intended to show the relative geometric dimensions of certain elements. Distance (a) represents the height of the cross flow manifold area 226. This is the distance between the top of the wafer holder (the position at which the substrate is mounted) and the plane of the top surface of the CIRP 206. Since the CIRP of FIG. 9 does not include steps or bumps, the top surface of the CIRP 206 is also the CIRP plane, as defined herein. In a particular embodiment, this distance is about 2-10 mm, for example about 4.75 mm. The distance (b) represents the distance between the exposed wafer surface and the lowermost surface of the wafer holder (the bottom surface of the wafer holding cup). In a particular embodiment, this distance is about 1 to 4 mm, for example about 1.75 mm. The distance (c) represents the height of the fluid gap between the upper surface of the cross flow limiting ring 210 and the bottom of the cup 254. This air gap between the limiting ring 210 and the bottom of the cup 254 provides a space such that the cup 254 can be rotated during plating, which typically prevents fluid from leaking out of the air gap. As small as possible to confine fluid within the cross flow manifold region 226. In some embodiments, the fluid gap is about 0.5 mm high. Distance (d) is representative of the height of the fluid channel for delivering the catholyte transverse flow of the crossflow manifold 226. Distance (d) includes the height of the cross flow restriction ring 210. In a particular embodiment, the distance (d) is about 1 to 4 mm, for example about 2.5 mm. Also shown in FIG. 9 is one of the cross flow injection manifold 222, the showerhead plate 242 with the distribution holes 246, and the directional fins 266 attached to the cross flow restriction ring 210.

The devices disclosed herein may be configured to perform the methods described herein. Suitable devices include hardware as described and illustrated herein, and one or more controllers having instructions for controlling process operations according to the present invention. Among other things, the apparatus positions the wafer in the cup 254 and cone, positions the wafer relative to the channeled ion resistant plate 206, rotates the wafer, delivers catholyte to the cross flow manifold 226, and cathodes to the CIRP manifold 208. Fluid delivery, delivery of catholyte to cross flow injection manifold 222, resistance / position of fluid conditioning rod 270, delivery of current to anode and wafer and any other electrodes, mixing of electrolyte components, timing of delivering electrolyte , One or more controllers to specifically control inlet pressure, plating cell pressure, plating cell temperature, wafer temperature, as well as other parameters of the particular process that the process tool performs.

  The system controller typically includes one or more memory devices and one or more processors configured to execute instructions to perform the method according to the present invention. The processor may include a central processing unit (CPU) or computer, analog and / or digital input / output connections, stepper motor controller boards, and other similar components. A machine readable medium containing instructions for controlling process operations according to the present invention may be coupled to the system controller. Instructions for implementing the appropriate control operations are executed on this processor. These instructions may be stored in a memory device associated with the controller or may be provided over a network. In particular embodiments, a system controller executes system control software.

  System control software may be configured in any suitable manner. For example, various process tool component subroutines or control objects may be written to control the operation of process tool components necessary to execute various process tool processes. The system control software may be encoded in any suitable computer readable language.

  In some embodiments, system control software includes input / output control (IOC) permutation instructions to control the various parameters described above. For example, each stage of the electroplating process may include one or more instructions for the system controller to perform. Instructions for setting process conditions for the immersion stage may be included in the corresponding immersion recipe stage. In some embodiments, the electroplating recipe steps may be arranged sequentially such that all the instructions for the electroplating process step are performed simultaneously by this process step.

  Other computer software and / or programs may be used in some embodiments. Some examples of programs or programs for this purpose include substrate positioning programs, electrolyte composition control programs, pressure control programs, heater control programs, and potential / current supply control programs.

  In some cases, the controller controls one or more of the following functions: wafer immersion (translation, tilting, rotation), transport of fluid between tanks, etc. Wafer immersion may be controlled, for example, by orienting and moving the wafer lift assembly, wafer tilt assembly and wafer rotation assembly as desired. The controller may control transport of fluid between the tanks, for example, by opening and closing particular valves and turning particular pumps on / off. The controller may be based on the timing of sensor output (eg when current, current density, potential, pressure etc reach a certain threshold), operation (eg opening a valve at a certain point in the process) or from the user These aspects may be controlled based on the received instructions.

  The above-described apparatus / process may be used, for example, with lithographic patterning tools or processes for the manufacture or manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, and the like. Typically, although not necessarily, such tools / processes are used or operated together in a typical fabrication facility. Lithographic patterning of a film involves some or all of the following steps, each of which can be performed using a number of possible tools: (1) Workpiece or substrate using a spin-on tool or a spray-on tool Application of the photoresist onto the material; (2) curing of the photoresist using a hot plate or oven or a UV curing tool; (3) visible light or UV light or X-ray light of the photoresist with a tool such as a wafer stepper (4) development of the resist to selectively remove the resist and pattern it using a tool such as a wet bench; (5) by using a dry etching tool or a plasma assisted etching tool, Transfer of resist patterns onto films or workpieces of the film; and (6) RF or microwave plastic Using a tool such as Ma resist stripper, removal of the resist.

[Characteristics of Ion Resistance Element with Channel]
[Electrical function]
In certain embodiments, the channeled ion resistant element approaches a substantially constant and uniform current source in the vicinity of the substrate (cathode), which may itself be referred to as a high resistivity virtual anode (HRVA) in some cases . Usually, the CIRP is placed in close proximity to the wafer. In contrast, the anode, which is also proximal to the substrate, is not capable of delivering a substantially constant current density to and across the wafer, but merely supports a constant potential surface at the anode metal surface. This allows the current to be maximized, while reducing the net resistance from the anode plane to the terminals (eg to the peripheral contact points on the wafer). Thus, although the channeled ion resistant element may have been referred to as a high resistance virtual anode (HRVA), this does not imply that the two can be interchanged electrochemically. Under optimal operating conditions, the CIRP will be closer to the virtual uniform current source, possibly better described as a virtual uniform current source, and a nearly constant current will be supplied across the top plane of the CIRP. It is certainly possible to regard CIRP as a "virtual current source", ie it is the plane in which the current is generated and hence the position or source from which the anode current is generated, so "virtual anode" As can be considered, the CIRP provides substantially better wafer uniformity as compared to having substantially uniform current across the surface, and more advantageous, metallic anodes located at the same physical location. (Relative to the electrolyte and to the outer region of CIRP) are relatively high ionic resistance. The resistance of the plating to ionic current is an increase in the specific resistance of the electrolyte contained in the various channels in the plating (often with the same or nearly the same resistance as the resistance of the catholyte), With increasing plating thickness and decreasing porosity (for example, the partial cross-sectional area through which the current passes is reduced by having a smaller number of holes of the same diameter or a smaller number of holes) Increase.

[Construction]
The CIRP is a disc of material about 2 to 25 mm thick, for example 12 mm. The CIRP has a large number of micro-sized (typically less than 0.04 inches) through holes that occupy less than about 5% of the volume of the CIRP, said through holes being spatially and ionically separated from each other Thus, in many but not all implementations, these through holes do not form interconnect channels within the CIRP body. Such through holes may be referred to as "non-communicating through holes". They typically extend in one direction, which is usually, but not necessarily, perpendicular to the plating surface of the wafer (in some embodiments, the non-communicating holes are CIRP's). At an angle to the wafer approximately parallel to the front surface). Usually, all the through holes are substantially parallel to one another. In some embodiments, the thickness of the CIRP plate is non-uniform. The CIRP plate may be thicker at the edge than at the center, or vice versa. The surface of the CIRP furthest from the wafer may be shaped to match the flow and ionic flow resistance of the plating. The holes are usually arranged in a square array, but other arrangements are possible which result in a spatially uniform density or holes. Of course, the density of the holes may also be increased, for example by increasing (or decreasing) the center-to-edge spacing of the CIRP, thereby increasing (or decreasing) the resistance depending on the distance from the center of the CIRP. You can change it. In other cases, it is a misaligned swirl pattern. The vias reshape both the ion current and fluid flow parallel to the surface, and straighten the path of both the current and fluid flow to the wafer surface, so that the channels are in three dimensions. It differs from the three-dimensional network of pores that extend and form interconnected pore structures. However, in certain embodiments, pore plates having such an interconnected network of pores may be used in place of CIRP. If the distance from the plate upper surface to the wafer is small (eg, about 1/10 of the size of the wafer radius, eg, about 5 mm or less), branching of both current and fluid flow is limited locally and into the CIRP channel It is transmitted and aligned.

In certain embodiments, the CIRP comprises a step that is approximately coextensive with the diameter of the substrate (eg, the diameter of the step may be within about 5% of the diameter of the substrate, such as about 1%). The step is defined as a raised portion on the substrate facing side of the CIRP, which is approximately coextensive with the substrate to be plated. The stepped portion of the CIRP also includes through holes that mate with the through holes of the major portion of the CIRP. An example of this embodiment is shown in FIGS. 10A and 10B. The purpose of the step 902 is to reduce the height of the cross flow manifold 226 to increase the rate of movement of fluid in this area without increasing the volumetric flow rate. The step 902 can also be considered as a plateau area and may be implemented as a bulge area of the CIRP 206 itself.

In many cases, the diameter of the step 902 should be slightly smaller than the inner diameter of the substrate holder 254 and the cross flow limiting ring 210 (for example, the outer diameter of the step may be about 2 to 10 mm smaller than the inner diameter of the substrate holder ). Without this difference in diameter (illustrated as distance (f)), an undesirable pinch point may be formed between the cup holder 254 and / or the cross flow restriction ring 210 and the step 902, here the cross flow manifold 226. It is difficult or impossible for the fluid to flow upwards into it. In such cases, it may be undesirable for the fluid to escape from the fluid gap 904 above the cross flow restriction ring 210 and below the bottom surface of the substrate holder / cup 254. This fluid gap 904 is provided for practicality, as the substrate holder 254 should be rotatable relative to the CIRP 206 and other elements of the plating cell. It is preferred to minimize the amount of catholyte that escapes through the fluid gap 904. The step 902 may have a height of about 2-5 mm, for example about 3-4 mm, which corresponds to the height of the cross flow manifold which is less than about 1-4 mm, or about 1-2 mm or about 2.5 mm. You may

If a step is present, the height of the cross flow manifold is measured as the distance between the plated surface of the wafer and the raised step 902 of CIRP 206. This height is shown as distance (e) in FIG. 10A. Although the substrate is not shown in FIG. 10A, it should be understood that the plated surface of the substrate rests on the lip seal portion 906 of the substrate holder 254. In certain implementations, the steps have rounded edges so that the fluid can flow better into the cross flow manifold. In this case, the step may include a transition area of about 2 to 4 mm wide, with the step surface being rounded / slanted. Although a rounded step is not shown in FIG. 10A, the distance (g) represents where such a transition region is located. Radially inward of this transition region, the CIRP may be flat. The non-bulging portion of the CIRP may extend around the entire circumference of the CIRP as shown in FIG. 10B.

In other embodiments, the CIRP may include a series of ridges on its upper surface. The ridges are defined as structures disposed / attached on the substrate facing side of the CIRP extending into the cross flow manifold between the CIRP plane and the wafer. The CIRP plane (also referred to as the Ion Resistive Element Plane) is defined as the upper surface of the CIRP excluding any ridges. The CIRP plane is where the ridges are attached to the CIRP and also where fluid flows out of the CIRP to the cross flow manifold. An example of this embodiment is shown in FIGS. 1A and 11. FIG. 1A is an isometric view of a CIRP 150 with ridges 151 oriented perpendicular to the direction of cross flow . FIG. 11 is an enlarged view of the inlet portion of a plating apparatus having a CIRP 206 with ridges 908. The CIRP 206 may include a peripheral area where no ridges are located, which allows the catholyte to move upward to the cross flow manifold 226. This peripheral area without the ridges may have a width as described above for the distance between the step and the cup holder. In many cases, the ridges are substantially coextensive with the plated surface of the substrate to be plated (eg, the diameter of the ridge region of CIRP is within about 5% or about 1% of the diameter of the substrate) May be

The ridges may be oriented in a variety of ways, but in many implementations the ridges are in the form of long thin ribs disposed between the rows of holes in the CIRP, and the ridges in the longitudinal direction cross flow It is oriented to be perpendicular to the cross flow through the manifold. An expanded view of a CIRP with long thin ridges disposed between the rows of holes in the CIRP is shown in FIG. The ridges modify the flow field adjacent the wafer to improve mass transport to the wafer and to improve mass transport uniformity across the surface of the wafer. In some cases, the ridges may be machined into existing CIRP plates, or may be formed simultaneously when fabricating a CIRP. As shown in FIG. 12, the raised portion may be disposed so as not to block the existing one-dimensional CIRP through hole 910. In other words, the width of the ridges 908 may be smaller than the distance between each row of holes 910 in the CIRP 206. In one embodiment, the holes 910 of the CIRP are spaced 2.69 mm between their centers, and the diameter of the holes is 0.66 mm. Thus, the width of the raised portion is less than about 2 mm (2.69-2 × (0.66 / 2) mm = 2.03 mm). In certain cases, the width of the ridges may be less than about 1 mm. In certain cases, the ridges have a length: width aspect ratio of at least about 3: 1.

In many implementations, the ridges are such that their length direction is perpendicular or substantially perpendicular to the cross flow direction (sometimes referred to herein as the "z" direction) across the plane of the wafer. It is oriented to be In certain cases, the ridges are oriented at different angles or different series of angles.

  Various shapes, sizes and arrangements of ridges may be used. In some embodiments, the ridges have a plane substantially perpendicular to the plane of the CIRP, and in other implementations, the ridges have a plane positioned at an angle to the plane of the CIRP . In a further implementation, the ridges may be shaped so as not to have any flat surface. In some embodiments, ridges of various shapes and / or sizes and / or orientations may be used.

FIG. 13 shows an example of the shape of the ridge as a cross-sectional view of ridge 908 on CIRP 206. In some implementations, the ridges are generally rectangularly shaped. In other implementations, the ridges are triangular, cylindrical or some combination thereof. The ridges may be generally rectangular with a machined triangular tip. In certain embodiments, the ridge may include a hole extending therethrough substantially parallel to the direction of cross flow across the wafer.

  FIG. 14 shows several examples of ridges with different types of through holes. The through holes may also be referred to as flow relief structures, notches, notches. The through holes help to disrupt the flow pattern so that the flow is convoluted in all directions (x, y and z). Example (a) shows a ridge having a top cut out in a rectangular pattern, example (b) shows a ridge having a bottom cut out in a rectangular pattern, example (c) cuts out in a rectangular pattern Example (d) shows a ridge having a series of holes cut out in a circular / elliptical pattern, Example (e) shows a series cut out in a rhomboid pattern Example (f) shows ridges with top and bottom alternately cut off in a trapezoidal pattern. The holes may be horizontal in a row with respect to one another or may be offset from one another as shown in examples (d) and (f).

FIG. 15 shows an example of a ridge 908 with alternating types of notches similar to the embodiment of example ( f ) of FIG. Here, two types of notches called first notch 921 and second notch 922 are used. In this embodiment, the first notch 921 is at the bottom of the ridge 908 and the second notch 922 is at the top of the ridge 908. The entire ridge may have a height (a) of about 1 to 5 mm and a thickness (b) of about 0.25 to 2 mm. The first notch may have a height (c) of about 0.2 to 3 mm and a length (d) of about 2 to 20 mm. A second notch 922 disposed on top of the ridge 908 may also have a height (e) of about 0.2 to 3 mm and a length (f) of about 2 to 20 mm. The distance (g) between adjacent first notches 921 (i.e., the distance between first notches 921) may be about 4 to 50 mm. The distance between adjacent second notches 922 (i.e. the spacing between second notches 922) (h) may also be about 4 to 50 mm. These dimensions are intended to aid understanding and are not intended to be limiting. The wafer plane (w) is shown above the ridges 908. The cross flow manifold 226 is between the base of the ridge 908 attached to the CIRP and the wafer plane (w).

FIG. 16 illustrates an embodiment of CIRP 206 having ridges 908 of the type shown in FIG. Also shown in FIG. 16 is a cross flow restriction ring 210. It will be appreciated by those skilled in the art that many different types of ridges and notches may be used within the scope of the embodiments disclosed herein.

Some implementations utilize ridges with voids (sometimes referred to as non-raised voids) such that two or more separate / discontinuous ridges are placed in the same row of holes in the CIRP You may FIG. 17 shows an example of a CIRP 206 having ridges 908 with non-raised air gaps 912. The voids 912 of the ridges 908 may be designed such that they are not substantially aligned with one another in the cross flow direction. For example, in FIG. 17, the air gaps 912 do not align with one another between adjacent rows of ridges 908. Voids 912 Such misalignments along with this purpose can help to promote mixing of the impinging flow and the cross flow in the cross flow manifold to promote uniform plating results.

  In some implementations, there is one ridge between each row of holes in the CIRP, and in other implementations there may be fewer ridges. For example, in certain embodiments, there may be ridges, such as every two or four rows of holes in the CIRP. In further embodiments, the locations of the ridges may be more random.

One parameter suitable for optimizing the ridge is the height of the ridge, or related thereto, the distance between the top of the ridge and the bottom of the wafer surface, or from CIRP to the wafer It is the ratio of the height of the ridge to the height of the channel. In a particular implementation, the height of the ridges is about 2-5 mm, for example 4-5 mm. The distance between the top of the ridges and the bottom of the wafer may be less than about 1 to 4 mm, such as about 1 to 2 mm or about 2.5 mm. The ratio of the height of the ridges to the height of the cross flow manifold may be about 1: 3 to 5: 6. If ridges are present, the height of the cross flow manifold is measured as the distance between the plated surface of the wafer and the plane of the CIRP excluding any ridges.

FIG. 18 is an enlarged cross-sectional view of CIRP 206 with ridges 908 positioned between holes 910 of CIRP 206. Transverse flow manifold 226 occupies the space between the wafer plane (w) and the CIRP plane 914. The height of the cross flow manifold 226 may be about 3 to 8 mm, for example about 4 to 6 mm. In a particular embodiment, this height is about 4.75 mm. The ridges 908 are positioned between the rows of holes 910 of the CIRP 206 and have the above-described height (b) less than the height (a) of the cross flow manifold 226.

FIG. 19 is a simplified top view of an alternative embodiment of CIRP 206 having ridges 908 oriented differently. In this embodiment, each ridge 908 consists of two segments 931 and 932. For the sake of clarity, only one ridge and one set of ridge segments are referenced. Segments 931 and 932 are oriented perpendicular to one another and have identical or substantially similar lengths (eg, within about 10% of each other). In other embodiments, these segments 931 and 932 may be oriented at different angles relative to one another and may have different lengths. In a further embodiment, the two segments 931 and 932 may be separated from each other, such that each of two (or more) separate types of ridges oriented at an angle to the cross flow Exists. In FIG. 19, the direction of the cross flow is from left to right as shown in the figure. Each segment 931 and 932 of ridges 908 is oriented at an angle (a) and an angle (b) with respect to the cross flow . The line separating angles (a) and (b) is intended to represent the direction of the entire cross flow . In certain cases, these angles are identical or substantially similar (e.g., within about 10% of the other). This embodiment differs from, for example, that shown in FIG. 1A, as the raised portions 908 are not independently oriented in a direction perpendicular to the cross flow in this embodiment. However, because the angles (a) and (b) are substantially similar, and because the lengths of the ridge segments are substantially similar, the ridges, on average, are perpendicular to the cross flow direction. It can be considered as being oriented in

  In various cases, the CIRP is a disc made of a rigid, non-porous insulating material with ionic and electrical resistance. This material is chemically stable in the plating solution used. In certain cases, CIRP may be a ceramic material (eg, aluminum oxide, stannic oxide, titanium oxide or a mixture of metal oxides) or a plastic material (eg, polyethylene, polypropylene, etc.) having about 6000 to 12000 unconnected through holes. Polyvinylidene difluoride (PVDF), polytetrafluoroethylene, polysulfone, polyvinyl chloride (PVC), polycarbonate etc.). In many embodiments, the disk is substantially coextensive with the wafer (e.g., a CIRP disk has a diameter of about 300 mm when used with a 300 mm wafer) and in close proximity to the wafer, e.g. In the electroplating apparatus which is directly below the wafer. Preferably, the plated surface of the wafer is within about 10 mm, more preferably within about 5 mm, of the CIRP surface. For this purpose, the top surface of the channeled ion resistant plate may be flat or substantially flat. In certain cases, both the top and bottom surfaces of the channeled ion resistant plate are flat or substantially flat.

  Another feature of the CIRP is the diameter or major dimension of the through hole and the relationship between this diameter or dimension and the distance between the CIRP and the substrate. In certain embodiments, the diameter of each through hole (or most of the through holes or the average diameter of the through holes) is less than or equal to the approximate distance from the surface of the wafer being plated to the closest surface of the CIRP. Thus, in such embodiments, if the CIRP is within about 5 mm of the wafer surface to be plated, the diameter or major dimension of the through hole does not exceed about 5 mm.

  As mentioned above, the overall ionic and flow resistance of the plate is dependent on both the thickness of the plate and the overall porosity (percentage of the area through which the flow can pass through the plate) and the size / diameter of the pores It depends. Plates with low porosity will have high impact flow rates and ionic resistance. Comparing plates with the same porosity, plates with small diameter one-dimensional holes (and thus many one-dimensional holes) can spread more independent current sources (more over the same void) Because it acts as a source, it has a finer and more uniform current distribution on the wafer and also has a higher total pressure drop (high viscous flow resistance).

  However, in certain cases, the ion resistant plate is porous as described above. The pores of the plate do not form independent one-dimensional channels, but may instead form a network of through-holes, which may or may not be interconnected. It is understood that the terms "channeled ion resistant plate (CIRP)" and channeled ion resistant element as used herein are intended to include such embodiments unless otherwise noted. I want to be

[Vertical flow through the through hole]
An ion resistant but ion permeable element (CIRP) 206 is present in the vicinity of the wafer if the end effect is effective / related, such as when the current resistivity of the wafer seed layer is greater than the cell's catholyte. The end effect is substantially reduced and the radial plating uniformity is improved. CIRP also provides the ability to orient a substantially spatially uniform impinging flow of electrolyte upward at the wafer surface by acting as a flow diffusion manifold plate. Importantly, if the same element is placed far away from the wafer, the improvement in ion flow uniformity and flow is greatly diminished or does not occur.

  Furthermore, non-communicating through holes do not allow lateral movement of ion flow or fluid movement within the CIRP, so movement of current and flow from the center to the edge is impeded within the CIRP, which results in radial plating It leads to a further improvement of the uniformity.

  Note that in some embodiments, the CIRP plate can be used primarily or exclusively as an in-cell electrolyte flow resistance, flow control and flow shaping element and may be referred to as a turboplate. Whether this plate matches radial deposition uniformity, for example by balancing end effects and / or by adjusting the mechanical resistance of the plating additive added to the flow in the electric field or cell Such names may be used regardless of Thus, for example, in TSV and WLP electroplating where the thickness of the seed metal is generally large (e.g. thickness> 1000. Metal) is deposited at very high speed, uniform distribution of electrolyte flow is very important, while , Radial non-uniformity due to ohmic voltage drop within the wafer seed (at least in part due to reduced importance of center-to-edge non-uniformity when using thicker seed layer) The need to compensate for sex control may be less. Thus, the CIRP plate can be referred to as both an ion resistant and ion permeable element and a flow shaping element, changing the flow of the ion flow, changing the convection of the material, or both It can provide a correction function.

[Distance between wafer and plate with channel]
In certain embodiments, the wafer holder and associated positioning mechanism hold the rotating wafer in close proximity to the parallel upper surface of the channeled ion resistant element. During plating, the substrate is generally positioned to be parallel or substantially parallel (eg, within about 10 °) to the ion resistant element. The substrate may have certain features thereon, but in determining whether the substrate and the ionically resistant element are substantially parallel, only the approximately flat shape of the substrate is considered .

  Typically, the separation distance is about 1-10 mm, or about 2-8 mm. This short distance between the plate and the wafer creates a plating pattern on the wafer, which is related to the proximity "imaging" of the independent holes in this pattern, especially near the center of rotation of the wafer. In such situations, a pattern of plating rings (in thickness or texture of plating) may occur near the center of the wafer. To avoid this phenomenon, in some implementations, the independent holes in the CIRP (especially at the center and near the center of the wafer) are of particularly small size, for example less than about one-fifth of the plate-to-wafer gap Can be configured to have The small size of the pores, coupled with the rotation of the wafer, enables time averaging of the flow velocity of the impinging flow generated as a jet from the plate, reducing the small scale (eg micrometer level) non-uniformity Or avoid. Notwithstanding the above noted, and depending on the properties of the plating bath used (eg, the particular metal deposited, conductivity, and bath additives used), in some cases, deposition is time-averaged exposure And a finely non-uniform pattern (eg, forming a central ring), as a proximity imaging pattern of varying thickness (eg, in a “bulls-eye” shape around the center of the wafer), and corresponding to the pattern of discrete holes used Can be easily generated. Such may occur if the limited pattern of holes produces an impinging flow pattern that is non-uniform and affects deposition. In this case, by introducing lateral flow across the wafer center, and / or modifying the regular pattern of holes at and / or near the center, micro non-uniformities that would otherwise occur. It has been found that any sign of sexuality can be largely eliminated.

[Porosity of plate with channel]
In various embodiments, the channeled ion resistant plate has sufficiently low porosity and pore size to provide viscous flow resistant back pressure and high vertical impingement flow rates at normal operating volumetric flow rates. In some cases, about 1 to 10% of the channeled ion resistant plate is an open area that allows fluid to reach the wafer surface. In certain embodiments, about 2-5% of the plate is the open area. In a specific embodiment, the open area of plate 206 is about 3.2%, and the effective total open cross-sectional area is about 23 cm 2.

[Pore size of plate with channel]
The porosity of the channeled ion resistant plate can be implemented in many different ways. In various embodiments, this may be implemented using multiple vertical holes of small diameter. In some cases, the plate does not have independent "perforated" holes, but is produced by a sintered plate of continuous porous material. An example of such a sintered plate is described in US Pat. No. 6,964,792 (Attorney Docket No. NOVLP 023), which is incorporated herein by reference in its entirety. In some embodiments, the diameter of the leading non-communicating hole is about 0.01 to 0.05 inches. In some cases, the diameter of the holes is about 0.02 to 0.03 inches. As mentioned above, in various embodiments, the holes have a diameter of up to about 0.2 times the air gap distance between the channeled ion resistant plate and the wafer. The holes generally have a circular cross-section but this is not necessarily the case. Furthermore, in order to simplify the configuration, all the holes in the plate may have the same diameter. However, this need not be the case and both the individual size and the local density of the holes may vary across the plate surface as may be required by specific requirements.

  By way of example, it may be advantageous to have for example at least about 1000 or at least about 3000 or at least about 5000 or at least about 6000 many small holes (9465 holes with a diameter of 0.026 inch) Known are rigid plates of suitable ceramic or plastic material (generally electrically insulating and mechanically robust material). As mentioned above, some designs have about 9000 holes. The porosity of the plate is typically less than about 5%, which reduces the total flow required to produce a high impact velocity. The use of smaller holes helps to create a larger pressure drop across the plate as compared to using larger holes, and helps create a more uniform upward flow through the plate.

  In general, the distribution of holes throughout the channeled ion resistant plate is of uniform density and not random. However, in some cases, the density of the holes may vary in particular in the radial direction. In certain embodiments, the holes have a higher density and / or larger diameter in the region of the plate that directs the flow to the center of the rotating substrate, as described more fully below. Furthermore, in some embodiments, the holes that orient the electrolyte at or near the center of the rotating wafer may induce flow at angles that are not perpendicular to the wafer surface. Furthermore, the pattern of holes in this area may have a random or partially random distribution of non-uniform plating "rings", thereby between a limited number of holes and the rotation of the wafer. Address possible interactions. In some embodiments, the density of the holes in the vicinity of the opening segment of the flow switching valve or the limiting ring is that of the holes in the region of the channeled ion resistant plate away from the opening segment of the attached flow switching valve or the limiting ring. Less than density.

  The configurations and / or approaches described herein are meant to be limiting in that they are exemplary in nature and that many variations are possible for these particular embodiments or examples. It should be understood that it should not be considered. The specific procedures or methods described herein may represent one or more of any number of processing strategies. Thus, the various acts illustrated may be performed in the order illustrated, in other orders, in parallel, or with some omissions. Likewise, the order of the processes described above may be changed.

  The subject matter of the present disclosure is a novel and non-obvious combination of the various processes, systems and configurations disclosed herein, as well as other features, functions, operations and / or properties, and any and all equivalents thereof. And partial combinations.

[Example and experiment]
The modeling results and the experimental results on the wafer suggest that the embodiments disclosed herein can significantly improve the uniformity of the plating process. FIG. 20 shows a summary of some experimental results for copper electroplating. Two different CIRP designs (with and without ridges) were tested for each of two different deposition rates.

The first CIRP design was a control design with no steps or bumps. The second CIRP design included a series of 2.5 mm high ridges positioned between adjacent rows of holes in the CIRP and oriented perpendicular to the cross flow . The height of the cross flow manifold was about 4.75 mm. The two copper deposition rates tested were 2.4 μm / min and 3.2 μm / min. In other words, the current delivered during each experiment was the level of current required to deposit metal on average at about 2.4 μm / min and 3.2 μm / min. The plating chemistry used in the experiment is SC40 chemistry from Enthone (West Haven, Conn.), Which has a sulfuric acid concentration of about 140 g / L, a cupric ion (Cu 2+) concentration of about 40 g / L (copper sulfate) Origin)). The concentrations of the R1 additive and the R2 additive in the catholyte were 20 mL / L and 12 mL / L, respectively. The flow rate of the catholyte was about 20 L / min. The substrate was rotated at a speed of about 4 RPM. The fluid gap between the upper surface of the cross flow restriction ring and the lower surface of the plating cup was about 0.5 mm. The plating process was performed at 30.degree. The post bump height was measured at a number of different locations across the surface of each wafer.

  In all cases, the bump height was somewhat thicker than near the edge of the wafer and somewhat thinner than near the center of the wafer. However, at both deposition rates, the thickness variation was smaller for the CIRP with ridges than for the control CIRP. Thus, the CIRP with ridges showed a clear improvement in the distribution of bump height, thickness. Coplanarity was substantially identical for the control and with the ridges, but under conditions of high mass transfer (eg, copper deposition rates> 4 μm) Is expected to be better. Die coplanarity is defined as (1/2 × (maximum bump height−minimum bump height) / average bump height) for a given die. The coplanarity of the wafers reported in FIG. 20 is the average of the coplanarity of all dies of a given wafer. In this case, there were approximately 170 dies on a particular test wafer.

  Further modeling results demonstrating the effectiveness of the ridges are contained in US Provisional Patent Application No. 61 / 736,499, which has already been incorporated herein by reference.

[Other embodiments]
While the above is a complete description of specific embodiments, various modifications, alternative constructions and equivalents may be used. Therefore, the above description and illustrations should not be construed as limiting the scope of the present invention as defined in the appended claims.
For example, the present invention may be realized by the following modes.
[Form 1]
An electroplating apparatus,
(A) an electroplating chamber configured to include an electrolyte and an anode during electroplating of a metal on a substantially planar substrate;
(B) a substrate holder configured to hold the substantially flat substrate such that the plated surface of the substrate is separated from the anode during electroplating;
(C) an ion resistant element,
(I) a plurality of channels extending through the ionically resistive element adapted to transport ions through the ionically resistive element during electroplating;
(Ii) a substrate facing side substantially parallel to the plated surface of the substrate and separated from the plated surface of the substrate by a gap;
(Iii) an ion resistant element comprising a plurality of ridges positioned on the substrate facing side of the ion resistant element;
(D) an inlet to the air gap for introducing a cross flow of the electrolyte into the air gap;
(E) an outlet of the cavity for receiving the cross flow of the electrolyte flowing in the cavity;
The electroplating apparatus, wherein the inlet and the outlet are positioned at substantially azimuthally opposite circumferential positions on the plating surface of the substrate during electroplating.
[Form 2]
The electroplating apparatus according to the first aspect, wherein
The air gap between the substrate facing side of the ion resistant element and the plated surface of the substrate was measured between the plated surface of the substrate and the plane of the ion resistant element Electroplating equipment, which is less than about 15 mm.
[Form 3]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, wherein the gap between the plated surface of the substrate and the top of the ridge is about 0.5 to 4 mm.
[Form 4]
The electroplating apparatus according to the first aspect, wherein
The electroplating apparatus, wherein the height of the raised portion is about 2 to 10 mm.
[Form 5]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, wherein the ridges are, on average, oriented substantially perpendicular to the direction of the cross flow of the electrolyte.
[Form 6]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus wherein at least some of the ridges have a length: width aspect ratio of at least about 3: 1.
[Form 7]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, wherein the ridges of at least two different shapes and / or sizes are present on the ion resistant element.
[Form 8]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, comprising at least some of the ridges, one or more notches through which electrolyte can flow during electroplating.
[Form 9]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, wherein at least some of the ridges comprise planes substantially perpendicular to the plane of the ion resistant element.
[Form 10]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, wherein at least some of the ridges comprise faces that are offset from the plane of the ionically resistive element by a non-perpendicular angle.
[Form 11]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, further comprising a triangular top on at least some of the ridges.
[Form 12]
The electroplating apparatus according to the first aspect, wherein
The ridges include at least a first ridge segment and a second ridge segment,
An electroplating apparatus, wherein the first and second ridge segments are each offset from the direction of the cross flow of the electrolyte by an angle that is substantially equal but opposite in sign.
[Form 13]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, wherein the ion resistant element is configured to shape an electric field and control the nature of the electrolyte flow near the substrate during electroplating.
[Form 14]
The electroplating apparatus according to the first aspect, wherein
Further comprising a lower manifold region positioned below the lower surface of the ion resistant element;
The electroplating apparatus, wherein the lower surface is opposite to the substrate holder.
[Form 15]
An electroplating apparatus according to mode 14, wherein
With the central electrolyte chamber
An electroplating apparatus, further comprising: one or more supply channels configured to deliver the electrolyte from the central electrolyte chamber to both the inlet and the lower manifold region.
[Form 16]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, further comprising a cross flow injection manifold in fluid communication with the inlet.
[Form 17]
The electroplating apparatus according to mode 10, wherein
The electroplating apparatus, wherein the cross flow injection manifold is at least partially defined by a cavity of the ion resistant element.
[Form 18]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, further comprising a flow limiting ring positioned across the perimeter of the ion resistant element.
[Form 19]
The electroplating apparatus according to the first aspect, wherein
An electroplating apparatus, further comprising a mechanism for rotating the substrate holder during plating.
[Form 20]
The electroplating apparatus according to the first aspect, wherein
The electroplating apparatus, wherein the inlet extends around an arc of about 90 to 180 degrees, around the periphery of the plated surface of the substrate.
[Form 21]
The electroplating apparatus according to the first aspect, wherein
A plurality of azimuthally distinct inlet segments within the inlet;
A plurality of electrolyte feed inlets, configured to deliver the electrolyte to the plurality of azimuthally distinct inlet segments;
An electroplating apparatus, further comprising: one or more flow control elements configured to independently control a plurality of volumetric flow rates of the electrolyte in the plurality of electrolyte supply inlets during electroplating.
[Form 22]
The electroplating apparatus according to the first aspect, wherein
The electroplating apparatus, wherein the raised portion is substantially coextensive with the plated surface of the substrate.
[Form 23]
The electroplating apparatus according to the first aspect, wherein
The inlet and the outlet are adapted to generate the cross flow of the electrolyte in the gap to generate or maintain a shear force on the plated surface of the substrate during electroplating. Electroplating equipment.
[Form 24]
The electroplating apparatus according to the first aspect, wherein
The ridges are oriented in a plurality of parallel rows,
The row comprises two or more discrete said ridges separated by non-raised voids,
An electroplating apparatus, wherein the non-raised voids of adjacent rows are substantially not aligned with one another in the direction of the cross flow of the electrolyte.
[Form 25]
An electroplating apparatus,
(A) an electroplating chamber configured to include an electrolyte and an anode during electroplating of a metal on a substantially planar substrate;
(B) a substrate holder configured to hold the substantially flat substrate such that the plated surface of the substrate is separated from the anode during electroplating;
(C) an ion resistant element,
(I) a plurality of channels extending through the ionically resistive element adapted to transport ions through the ionically resistive element during electroplating;
(Ii) a substrate facing side substantially parallel to the plated surface of the substrate and separated from the plated surface of the substrate by a gap;
(Iii) a step positioned on the substrate facing side of the ion resistant element, the step having a height and a diameter, the diameter of the step substantially corresponding to the plating surface of the wafer The step and the height and the diameter of the step are sufficient to allow the electrolyte to flow under the substrate holder, over the step and into the void during plating. Ion resistant elements, including small steps
(D) an inlet to the space for introducing the electrolyte into the space;
(E) an outlet of the gap for receiving the flow of the electrolyte flowing in the gap;
The inlet and the outlet are adapted to generate the cross flow of the electrolyte in the gap to generate or maintain a shear force on the plated surface of the substrate during electroplating. Electroplating equipment.
[Form 26]
A channeled ion resistant plate for use in an electroplating apparatus for plating material on a semiconductor wafer of standard diameter, comprising:
A plate having a thickness of about 2 to 25 mm, which is approximately coextensive with the plated surface of the semiconductor wafer;
At least about 1000 non-communicating through holes extending through the thickness of the plate, the through holes adapted to transport ions through the plate during electroplating;
A channeled ion resistant plate comprising: a plurality of ridges positioned on one side of the plate.
[Form 27]
A channeled ion resistant plate for use in an electroplating apparatus for plating material on a semiconductor wafer of standard diameter, comprising:
A plate having a thickness of about 2 to 25 mm, which is approximately coextensive with the plated surface of the semiconductor wafer;
At least about 1000 non-communicating through holes extending through the thickness of the plate, the through holes adapted to transport ions through the plate during electroplating;
A channeled ion-resistant plate comprising: a step of a plate comprising a bulge of the plate in the central region of the plate and a non-bulge of the plate positioned at the periphery of the plate.
[Form 28]
A method for electroplating a substrate, comprising
(A) Receiving a substantially flat substrate in a substrate holder, wherein the plated surface of the substrate is exposed, and the substrate holder is for electroplating of the substrate of the substrate Receiving, configured to hold the substrate such that the plating surface is separated from the anode;
(B) immersing the substrate in an electrolyte;
Forming an air gap between the plated surface of the substrate and the plane of the ion resistant element;
The ion resistant element is at least substantially coextensive with the plated surface of the substrate,
The ion resistant element is adapted to transport ions through the ion resistant element during electroplating;
Immersing the ion-resistant element comprising a plurality of ridges on the substrate-facing side of the ion-resistant element, the ridges being substantially coextensive with the plated surface of the substrate ,
(C) (i) into the cavity from the side inlet and out of the side outlet; and (ii) from under the ion-resistant element through the ion-resistant element into the cavity Flowing the electrolyte into contact with the substrate in the substrate holder, into and out of the side outlet, the inlet and the outlet being open during electroplating Flowing the electrolyte, which is designed or configured to generate a cross flow of the electrolyte in a void;
(D) rotating the substrate holder;
(E) electroplating a material on the plated surface of the substrate while flowing the electrolyte as in (c).
[Form 29]
The method according to Form 28, wherein
The method wherein the air gap is less than about 15 mm as measured between the plated surface of the substrate and the plane of the ion resistant element.
[Form 30]
The method according to Form 28, wherein
The method wherein the air gap between the plated surface of the substrate and the top surface of the ridge is about 0.5 to 4 mm.
[Form 31]
The method according to Form 28, wherein
The side inlets are separated into two or more sections which are azimuthally separate and not in fluid communication,
The method wherein the flow of the electrolyte to the azimuthally distinct section of the inlet is independently controlled.
[Form 32]
The method according to Form 28, wherein
A flow directing element is positioned in the air gap;
The method wherein the flow directing element allows the electrolyte to flow in a substantially straight flow path from the side inlet to the side outlet.
[Form 33]
A method for electroplating a substrate, comprising
(A) Receiving a substantially flat substrate in a substrate holder, wherein the plated surface of the substrate is exposed, and the substrate holder is for electroplating of the substrate of the substrate Receiving, configured to hold the substrate such that the plating surface is separated from the anode;
(B) immersing the substrate in an electrolyte;
Forming an air gap between the plated surface of the substrate and the plane of the ion resistant element;
The ion resistant element is at least substantially coextensive with the plated surface of the substrate,
The ion resistant element is adapted to transport ions through the ion resistant element during electroplating;
The ion-resistant element comprises a step on the substrate facing side of the ion-resistant element, the step being positioned in the central region of the ion-resistant element and surrounded by the non-bulging portion of the ion-resistant element Yes, soaking and
(C) (i) from the side inlet into the air gap over the step and again into the air through the step; and (ii) the ion from below the ion resistant element Flowing the electrolyte into contact with the substrate in the substrate holder so as to pass through the resistive element into the void and out the step and out the side outlet. Flowing the electrolyte, wherein the inlet and the outlet are designed or configured to generate a cross flow of the electrolyte in the air gap during electroplating;
(D) rotating the substrate holder;
(E) electroplating a material on the plated surface of the substrate while flowing the electrolyte as in (c).

Claims (34)

An electroplating apparatus,
(A) an electroplating chamber configured to include an electrolyte and an anode during electroplating of a metal on a substantially planar substrate;
(B) a substrate holder configured to hold the substantially flat substrate such that the plated surface of the substrate is separated from the anode during electroplating;
(C) an ion resistant element,
(I) a plurality of channels extending through the ionically resistive element adapted to transport ions through the ionically resistive element during electroplating;
(Ii) a substrate facing side substantially parallel to the plated surface of the substrate and separated from the plated surface of the substrate by a gap;
(Iii) an ion resistant element comprising a plurality of ridges positioned on the substrate facing side of the ion resistant element;
(D) an inlet to the void for introducing a cross flow of the electrolyte across the void into the void;
(E) an outlet of the gap for receiving the cross flow of the electrolyte flowing in the gap;
The inlet and the outlet are positioned at substantially azimuthally opposite circumferential positions on the plating surface of the substrate during electroplating,
The electroplating apparatus, wherein the ridges are, on average, oriented substantially perpendicular to the direction of the cross flow of the electrolyte. The electroplating apparatus according to claim 1, wherein
The air gap between the substrate facing side of the ion resistant element and the plated surface of the substrate was measured between the plated surface of the substrate and the plane of the ion resistant element Electroplating equipment, which is less than about 15 mm. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, wherein the gap between the plated surface of the substrate and the top of the ridge is about 0.5 to 4 mm. The electroplating apparatus according to claim 1, wherein
The electroplating apparatus, wherein the height of the raised portion is about 2 to 10 mm. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus wherein at least some of the ridges have a length: width aspect ratio of at least about 3: 1. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, wherein the ridges of at least two different shapes and / or sizes are present on the ion resistant element. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, comprising at least some of the ridges, one or more notches through which electrolyte can flow during electroplating. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, wherein at least some of the ridges comprise planes substantially perpendicular to the plane of the ion resistant element. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, wherein at least some of the ridges comprise planes that are offset from the plane of the ionically resistive element by a non-perpendicular angle. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, further comprising a triangular top on at least some of the ridges. The electroplating apparatus according to claim 1, wherein
The ridges include at least a first ridge segment and a second ridge segment,
An electroplating apparatus, wherein the first and second ridge segments are each offset from the direction of the cross flow of the electrolyte by an angle substantially equal but opposite in sign. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, wherein the ion resistant element is configured to shape an electric field and control the nature of electrolyte flow near the substrate during electroplating. The electroplating apparatus according to claim 1, wherein
Further comprising a lower manifold region positioned below the lower surface of the ion resistant element;
The electroplating apparatus, wherein the lower surface is opposite to the substrate holder. The electroplating apparatus according to claim 13, wherein
An electroplating apparatus further comprising: a central electrolyte chamber; and one or more supply channels configured to deliver the electrolyte from the central electrolyte chamber to both the inlet and the lower manifold region. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, further comprising a cross flow injection manifold in fluid communication with the inlet. The electroplating apparatus according to claim 15, wherein
The electroplating apparatus, wherein the cross flow injection manifold is at least partially defined by a cavity of the ion resistant element. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, further comprising a flow limiting ring positioned across the perimeter of the ion resistant element. The electroplating apparatus according to claim 1, wherein
An electroplating apparatus, further comprising a mechanism for rotating the substrate holder during plating. The electroplating apparatus according to claim 1, wherein
The electroplating apparatus, wherein the inlet extends around an arc of about 90 to 180 degrees, around the periphery of the plated surface of the substrate. The electroplating apparatus according to claim 1, wherein
A plurality of azimuthally distinct inlet segments within the inlet;
A plurality of electrolyte feed inlets, configured to deliver the electrolyte to the plurality of azimuthally distinct inlet segments;
An electroplating apparatus, further comprising: one or more flow control elements configured to independently control a plurality of volumetric flow rates of the electrolyte in the plurality of electrolyte supply inlets during electroplating. The electroplating apparatus according to claim 1, wherein
The electroplating apparatus, wherein the raised portion is coextensive with the plated surface of the substrate. The electroplating apparatus according to claim 1, wherein
The inlet and the outlet are adapted to generate the cross flow of the electrolyte in the air gap to generate or maintain a shear force on the plated surface of the substrate during electroplating. Electroplating equipment. The electroplating apparatus according to claim 1, wherein
The ridges are oriented in a plurality of parallel rows,
The row comprises two or more discrete said ridges separated by non-raised voids,
An electroplating apparatus, wherein the non-raised voids of adjacent rows are substantially not aligned with one another in the direction of the cross flow of the electrolyte. An electroplating apparatus,
(A) an electroplating chamber configured to include an electrolyte and an anode during electroplating of a metal on a substantially planar substrate;
(B) a substrate holder configured to hold the substantially flat substrate such that the plated surface of the substrate is separated from the anode during electroplating;
(C) an ion resistant element,
(I) a plurality of channels extending through the ionically resistive element adapted to transport ions through the ionically resistive element during electroplating;
(Ii) a substrate facing side substantially parallel to the plated surface of the substrate and separated from the plated surface of the substrate by a gap;
(Iii) a step positioned on the substrate facing side of the ion resistant element, the step having a height and a diameter, the diameter of the step being the plated surface of the substrate and The height and the diameter of the step are sufficiently small to allow the electrolyte to flow under the substrate holder, over the step and into the air gap during plating; An ion resistant element, including a step
(D) an inlet to the space for introducing the electrolyte into the space;
(E) an outlet of the gap for receiving the flow of the electrolyte flowing in the gap;
The inlet and the outlet are adapted to create a cross flow of the electrolyte across the air gap in the air gap to create or maintain a shear force on the plated surface of the substrate during electroplating. Electroplating equipment to be adapted. A channeled ion resistant plate for use in an electroplating apparatus for plating material on a semiconductor wafer of standard diameter, comprising:
A plate having a thickness of about 2 to 25 mm, which is coextensive with the plated surface of the semiconductor wafer;
(I) at least about 1000 non-communicating through holes extending through the thickness of the plate, the through holes adapted to transport ions through the plate during electroplating, or ii) a three-dimensional channel network forming interconnected pore structures along the thickness direction of the plate;
And a plurality of ridges positioned on one side of the plate;
A channeled ion resistive plate, wherein the plurality of ridges are, on average, oriented substantially perpendicular to the direction of the cross flow of electrolyte on the channeled ion resistive plate in the electroplating apparatus. A channeled ion resistant plate for use in an electroplating apparatus for plating material on a semiconductor wafer of standard diameter, comprising:
A plate having a thickness of about 2 to 25 mm, which is coextensive with the plated surface of the semiconductor wafer;
(I) extending through the thickness of the plate, at least about 1000 non-communicating holes, adapted transmural hole to transport ions through said plate during electroplating, or, (Ii) a three-dimensional channel network forming pore structures connected to each other along the thickness direction of the plate ;
A channeled ion-resistant plate comprising: a step of a plate comprising a bulge of the plate in the central region of the plate and a non-bulge of the plate positioned at the periphery of the plate. A method for electroplating a substrate, comprising
(A) Receiving a substantially flat substrate in a substrate holder, wherein the plated surface of the substrate is exposed, and the substrate holder is for electroplating of the substrate of the substrate Receiving, configured to hold the substrate such that the plating surface is separated from the anode;
(B) immersing the substrate in an electrolyte;
Forming an air gap between the plated surface of the substrate and the plane of the ion resistant element;
The ion resistant element is at least substantially coextensive with the plated surface of the substrate,
The ion resistant element is adapted to transport ions through the ion resistant element during electroplating;
Immersing the ion resistant element comprising a plurality of ridges on the substrate facing side of the ion resistant element, the ridges coextensive with the plated surface of the substrate;
(C) (i) into the cavity from the side inlet and out of the side outlet; and (ii) from under the ion-resistant element through the ion-resistant element into the cavity Flowing the electrolyte into contact with the substrate in the substrate holder to enter and exit from the side outlet, the side inlet and the side outlet being electrically connected Designed or configured to create a cross flow of the electrolyte across the void in the void during plating, the plurality of ridges, on average, being substantially perpendicular to the direction of the cross flow of the electrolyte Flowing the electrolyte, which is oriented in
(D) rotating the substrate holder;
(E) electroplating a material on the plated surface of the substrate while flowing the electrolyte as in (c). 28. The method of claim 27, wherein
The method wherein the air gap is less than about 15 mm as measured between the plated surface of the substrate and the plane of the ion resistant element. 28. The method of claim 27, wherein
The method wherein the air gap between the plated surface of the substrate and the top surface of the ridge is about 0.5 to 4 mm. 28. The method of claim 27, wherein
The side inlets are separated into two or more sections which are azimuthally separate and not in fluid communication,
The method wherein the flow of the electrolyte to the azimuthally distinct sections of the side inlets is independently controlled. 28. The method of claim 27, wherein
A flow directing element is positioned in the air gap;
The method wherein the flow directing element allows the electrolyte to flow in a substantially straight flow path from the side inlet to the side outlet. A method for electroplating a substrate, comprising
(A) Receiving a substantially flat substrate in a substrate holder, wherein the plated surface of the substrate is exposed, and the substrate holder is for electroplating of the substrate of the substrate Receiving, configured to hold the substrate such that the plating surface is separated from the anode;
(B) immersing the substrate in an electrolyte;
Forming an air gap between the plated surface of the substrate and the plane of the ion resistant element;
The ion resistant element is at least coextensive with the plated surface of the substrate,
The ion resistant element is adapted to transport ions through the ion resistant element during electroplating;
The ion-resistant element comprises a step on the substrate facing side of the ion-resistant element, the step being positioned in the central region of the ion-resistant element and surrounded by the non-bulging portion of the ion-resistant element Yes, soaking and
(C) (i) from the side inlet into the air gap over the step and again into the air through the step; and (ii) the ion from below the ion resistant element Flowing the electrolyte into contact with the substrate in the substrate holder so as to pass through the resistive element into the void and out the step and out the side outlet. Flowing the electrolyte, wherein the side inlet and the side outlet are designed or configured to generate a cross flow of the electrolyte across the void in the void during electroplating;
(D) rotating the substrate holder;
(E) electroplating a material on the plated surface of the substrate while flowing the electrolyte as in (c). A channeled ion resistant plate for use in an electroplating apparatus for plating material on a semiconductor wafer of standard diameter, comprising:
A plate having a thickness of about 2 to 25 mm, which is coextensive with the plated surface of the semiconductor wafer;
(I) at least about 1000 non-communicating through holes extending through the thickness of the plate, the through holes adapted to transport ions through the plate during electroplating, or ii) A three-dimensional channel network forming interconnected pore structures along the thickness of the plate, adapted to transport ions through the plate during electroplating, or 3 Dimensional channel network,
A plurality of ridges positioned on one side of the plate, oriented in a plurality of parallel rows, wherein the plurality of parallel rows are separated by two or more non-raised gaps A channeled ion resistant plate comprising ridges, wherein the non-raised air gaps in adjacent rows are not aligned with one another in the direction of the cross flow of electrolyte on the channeled ion resistant plate in the electroplating apparatus . A channeled ion resistant plate for use in an electroplating apparatus for plating material on a semiconductor wafer of standard diameter, comprising:
A plate having a thickness of about 2 to 25 mm, which is coextensive with the plated surface of the semiconductor wafer;
(I) at least about 1000 non-communicating through holes extending through the thickness of the plate, the through holes adapted to transport ions through the plate during electroplating, or ii) A three-dimensional channel network forming interconnected pore structures along the thickness of the plate, adapted to transport ions through the plate during electroplating, or 3 Dimensional channel network,
A plurality of protuberances positioned on one side of the plate, the plurality of protuberances comprising a first protuberance segment and a second protuberance segment, the first protuberance The segment and the second ridge segment are each offset from the direction of the cross flow of the electrolyte by an angle that is equal but opposite in sign, the cross flow of the electrolyte being the ion with channeled ions in the electroplating apparatus A channeled ion resistant plate that flows through an air gap located above the resistive plate.