JP2005518670A - Method and composition for polishing a substrate - Google Patents

Abstract

Polishing compositions and methods for removing conductive material from a substrate surface are provided. In one aspect, the composition comprises an acid-based electrolyte system, one or more chelating agents, one or more corrosion inhibitors, one or more inorganic acid salts or organic acid salts, and one type. It includes a pH adjusting agent that gives a pH of about 3 to about 10, a polishing particle, one or more oxidizing agents, and a polishing promoting material selected from a combination thereof and a solvent. The composition includes a step of disposing a substrate having a conductive material layer formed thereon in a process apparatus including an electrode, supplying the composition between the electrode and the substrate, the electrode and the substrate And a step of supplying a conductive material from the conductive material layer, and a conductive material removing process.

Description

Explanation of related applications

  [0001] This application claims priority to US Provisional Patent Application No. 60 / 359,746, filed Feb. 26, 2002 [Attorney Docket No. 6505L], referred to as “copper CMP slurry for organic polymer particles”. And the disclosure of that application is incorporated herein by reference. This application is also a co-pending US patent application Ser. No. 10 / 032,275, filed Dec. 21, 2001, entitled “Polishing Composition and Treatment for Electrochemical Chemical Polishing” [Attorney Docket No. 5988. ] And "Platform planarization using electrochemical mechanical polishing", filed Jan. 3, 2002, copending US patent application Ser. No. 10 / 038,066 [Attorney Docket No. 5699]. This is a continuation-in-part application, and the disclosure content of both applications is incorporated herein.

Background of the Invention

Field of Invention
[0002] Embodiments of the invention relate to compositions and methods for removing conductive material from a substrate.

Background of related technology
[0003] Reliably manufacturing features smaller than half a micron and smaller is one of the key technologies for the next generation of large scale integrated circuits (VLSI) and ultra large scale integrated circuits (ULSI) of semiconductor devices. It is. However, driven by circuit technology constraints, the shrinking dimensions of interconnects in VLSI and ULSI technologies have placed additional demands on processing power. Reliable formation of interconnects is critical to the success of VLSI and ULSI and is critical to continued efforts to increase the circuit density and quality of individual substrates and dies.

  [0004] Multi-level interconnects are formed using techniques that sequentially deposit and remove material on the substrate surface that forms the features therein. As layers of material are sequentially deposited and removed, the top surface of the substrate becomes non-planar through its surface, requiring planarization before polishing. Planarization, or “polishing”, is a process in which material is removed from a substrate surface to form a substantially flat and flat surface. Planarization is the next lithography and processing that removes excessively deposited material and provides a rough surface, lumped material, crystal lattice damage, scratches, to provide a flat surface. And is useful for removing unwanted surface features and surface defects such as contaminated layers.

  [0005] Electrochemical mechanical polishing (ECMP) is one method of planarizing the surface of a substrate. ECMP removes conductive materials such as copper from the substrate surface by electrochemical “anode” dissolution while polishing a substrate with reduced mechanical wear compared to conventional chemical mechanical planarization (CMP) processes. Is. A typical ECMP system includes a substrate support and two electrodes disposed in a basin containing a polishing composition. The substrate is in electrical contact with one electrode and effectively becomes a material removal electrode during processing. In operation, metal atoms on the substrate surface are ionized by current from a potential source such as a power source connected to the two electrodes. Metal ions dissolve in the surrounding polishing composition.

  [0006] However, ECMP processes typically appear to have a reduced removal rate compared to conventional chemical mechanical polishing processes, and the pressure between the substrate and polishing pad is improved to improve the removal rate. Although the processing conditions were improved to increase the processing time, it did not give satisfactory results in increasing the removal rate, and in some cases resulted in excessive shaving and damage to the substrate surface. For example, increasing the polishing pressure on a substrate containing a material with a low dielectric constant (low-k dielectric constant) has been observed to cause defects on the deposited material such as delamination and scratches due to the shear force caused by the increased polishing pressure. It was done.

  [0007] Accordingly, there is a need for compositions and methods for removing conductive material from a substrate that minimizes substrate damage during the planarization process.

Summary of the Invention

  [0008] Aspects of the invention provide compositions and methods for removing conductive material by electrochemical polishing techniques. In one aspect, the composition comprises an acid-based electrolyte system, one or more chelating agents, one or more corrosion inhibitors, one or more inorganic acid salts or organic acid salts, At least a conductive material from a substrate surface comprising a pH modifier that provides a pH of from about 3 to about 10 and a polishing accelerator material selected from the group of abrasive particles, one or more oxidizing agents, and combinations thereof; and a solvent Supplied to remove

  [0009] In another aspect, the composition comprises depositing a substrate having a conductive material layer formed thereon in a process apparatus comprising a first electrode and a second electrode, wherein the substrate is a second electrode. The step in electrical contact with the electrode; supplying a composition between the first electrode and the substrate; providing a potential difference between the first electrode and the second electrode; and a conductive material layer And a method provided for processing a substrate comprising removing a conductive material from the substrate.

  [0010] In order that the above aspects of the invention may be obtained and understood in more detail, a more particular description of the embodiments of the invention briefly summarized above is provided by referring to the embodiments illustrated in the accompanying drawings. It is made by reference.

  [0011] However, the attached drawings are only illustrative of exemplary embodiments of the invention and are therefore not to be considered as limiting its scope, and the invention is not limited to other equally effective implementations. It should be noted that the form is also acceptable.

Detailed Description of the Preferred Embodiment

  [0013] In general, aspects of the present invention provide compositions and methods for removing at least conductive material from a substrate surface. The present invention is described as follows with reference to a planarization process for removing conductive material from a substrate surface by electrochemical mechanical polishing (ECMP).

  [0014] Terms used in this specification are intended to be those meanings commonly and routinely used by those skilled in the art unless otherwise defined. Chemical polishing is widely interpreted and includes, but is not limited to, planarizing a substrate surface using a chemical reaction. Electropolishing is widely interpreted and includes, but is not limited to, planarizing a substrate by application of electrochemical activity. Electrochemical mechanical polishing (ECMP) is widely interpreted and depends on the application of electrochemical activity, mechanical activity, or a combination of both electrochemical and mechanical activity to remove material from the substrate surface. Including planarizing the substrate.

  [0015] Anodic dissolution is widely interpreted and includes, but is not limited to, removing conductive material from the substrate surface and directly or indirectly applying an anodic potential difference to the substrate that is incorporated into the peripheral polishing composition. Not. Polishing compositions are widely interpreted and include, but are not limited to, compositions that provide ionic conductivity, and thus conductivity in a liquid medium. The volume or weight% of the electrolytic solution component in the polishing composition means% based on the volume with respect to the liquid composition component and% based on the weight with respect to the solid composition component.

One embodiment of the apparatus
[0016] FIG. 1 is a cross-sectional view illustrating one embodiment of a process cell 200 "turned down". The process cell 200 generally includes a basin 204 and a polishing head 202. The substrate 208 is held by the polishing head 202 and lowered into the basin 204 during processing in a prone (eg, backside up) direction. An electrolyte as described herein is flowed into the basin 204 and is in contact with the substrate surface and the pad assembly 222, while the polishing head 202 is positioned on the substrate 208 in contact with the pad assembly 222. To do. The basin 204 includes a pad assembly 222, a bottom 244, and a sidewall 246 that defines a container that houses the pad assembly 222. The sidewall 246 includes a port 218 formed to allow removal of the polishing composition from the basin 204 therethrough. Port 218 is coupled to a valve 220 that selectively drains or holds the polishing composition to basin 204.

  [0017] The substrate 208 and pad assembly 222 disposed within the basin 204 are moved relative to each other to provide a polishing operation (or an operation that improves plating uniformity). The polishing operation generally comprises at least one operation defined by drawing a trajectory, rotating, drawing a straight line or a curve, or a combination thereof among various other operations. The polishing operation can be accomplished by moving either or both of the polishing head 202 and / or the basin 204. The polishing head 202 may be stationary or driven to provide at least part of the relative movement between the basin 204 and the substrate 208 held by the polishing head 202. In the embodiment shown in FIG. 1, the polishing head 202 is coupled to a drive system 210. The drive system 210 moves the polishing head 202 at least by rotating, trajectory drawing, sweeping motion, or a combination thereof.

  [0018] The polishing head 202 typically holds the substrate 208 during processing. In one embodiment, the polishing head 202 includes a housing 214 that surrounds a bladder 216. The bladder 216 may be evacuated to create a vacuum therebetween while in contact with the substrate, thereby securing the substrate to the polishing head 202. The bladder 216 may additionally bulge to contact the pad assembly 222 held by the basin 204 and press the substrate. A retaining ring 238 is coupled to the housing 214 and circumscribes the periphery of the substrate 208 to prevent the substrate from slipping off the polishing head 202 during processing. One polishing head that can be adapted to benefit from the present invention is the TITANHEAD® carrier head available from Applied Materials, Inc., located in Santa Clara, California. Another example of a polishing head that can be adapted to benefit from the present invention is US Pat. No. 6,159,079 issued Dec. 12, 2001, which is incorporated by reference herein in its entirety. The disclosure of which is incorporated herein in its entirety.

  [0019] Basin 204 is typically a fluoropolymer, TEFLON® polymer, perfluoroalkoxy resin (PFA), polyethylene-based plastic (PE), sulfonated polyphenylethersulfone (PES), or electroplating or Manufactured from plastic such as other materials that are compatible or non-reactive with polishing compositions that can be used for electropolishing. Basin 204 is supported for rotation on base 206 by bearing 234. The drive system 236 is coupled to the basin 204 and rotates the basin 204 during processing. The catch basin 228 is disposed on the base 206 and circumscribes to collect a processing liquid such as a polishing composition that flows out of a port 218 disposed through the basin 204 during and / or after processing.

  [0020] The polishing composition dispensing system 232 is generally located adjacent to the basin 204. Polishing composition dispensing system 232 includes a nozzle or outlet 230 coupled to polishing composition source 242. Outlet 230 allows polishing composition or other processing liquid to flow from polishing composition source 242 into basin 204. During processing, the polishing composition generally provides an electrical path to drive an electrochemical process that applies a potential difference to the substrate 208 and removes and / or deposits material on the substrate 208. Alternatively, the polishing composition dispensing system supplies the polishing composition through the bottom 244 of the processing vessel and causes the polishing composition to flow through the pad assembly so that the polishing pad and substrate are in contact. Alternatively, the recirculation system is used to recover and reuse the polishing composition. Further, the circulation system can be used to extend the effective manufacturing life of the polishing composition for the same or additional processing steps.

  [0021] Optionally, the conditioning device 250 shown in FIG. 1 may be provided proximate to the basin 204 to condition or regenerate the pad assembly 222 periodically. Conditioning device 250 typically includes an arm 252 that is coupled to a post 254 that adjusts position across pad assembly 222 and scans conditioning element 258. Conditioning element 258 is coupled to arm 252 by shaft 256 to allow clearance between arm 252 and the side wall of container 204, but conditioning element 258 is pushed down to contact pad assembly 222. Conditioning element 258 is typically a diamond or silicon carbide disk that is patterned to improve the surface operation of pad assembly 222 to a predetermined surface condition / state that improves processing uniformity. May be. One conditioning element 258 that can be adapted to benefit from the present invention is described in US patent application Ser. No. 09 / 676,280 filed Sep. 28, 2000 by Li et al. Incorporated herein to a degree consistent with the claimed aspects and description.

  [0022] The power source 224 is coupled to the pad assembly 222 by wires 223A, 223B. The power source 224 provides a potential difference to the pad assembly 222 to drive the electrochemical process as described below. 223A and 223B are wired through a slip ring 226 disposed below the basin 204. Slip ring 226 allows a continuous electrical connection to rotate basin 204 between power source 224 and pad assembly 222. The wires 223A and 223B are wires, tapes, or other conductors that are compatible with the treatment liquid or are coated or coated to protect the wires 223A and 223B from the treatment liquid. Examples of materials that can be used for the electric wires 223A and 223B include copper, graphite, titanium, platinum, gold, and HASTEROY®, which are insulated among other materials. The coating disposed around the wire may include a polymer such as fluorocarbon, PVC, polyamide.

  [0023] Since the pad assembly 222 includes elements comprising both the anode and cathode of an electrochemical cell, both anode and cathode simply remove the used pad assembly 222 from the basin 204 and new electrical to the basin 204. It is replaced at the same time by inserting a new pad assembly 222 having a support component.

  The illustrated pad assembly 222 includes a conductive pad 203 that is coupled to a backing 207. The backing 207 can be coupled to the electrode 209. A dielectric insert (not shown) can be placed between the conductive pad 203 and the backing 207 or electrode 209 to regulate the flow of electrolyte through all or part of the conductive pad. The conductive pad 203 is used so as to give a uniform potential difference to the substrate surface without using a conventional potential difference supply device such as an edge contact portion. The electrode 209 is generally applied with a potential difference as a cathode through a connection to a power source 224 via an electric wire, for example, an electric wire 223A, and the conductive pad 203 and the substrate are applied with a potential difference as an anode for anodic dissolution in the ECMP process.

  [0025] Typically, the conductive pad 203, backing 207, and possibly dielectric insert, and electrode 209 form a single body that allows removal and replacement of the pad assembly 222 from the container 204. Fixed together. Typically, the conductive pad 203, the backing 207, and in some cases, the dielectric insert, and the electrode 209 are bonded or bonded together. Alternatively, the conductive pad 203, the backing 207, and in some cases, the dielectric insert, and the electrode 209 may be other methods including, but not limited to, sewing, lashing, heat fitting, riveting, screwing, clamping, etc. Can be combined by combination. An example of a conductive pad 203 is more fully disclosed in US patent application Ser. No. 10 / 033,732, filed Dec. 27, 2001, the disclosure of which is consistent with the aspects and disclosure claimed herein. To this extent, it is incorporated herein by reference.

  [0026] The face down polishing apparatus is referred to as "substrate polishing method and apparatus", US patent application Ser. No. 10 / 151,538 filed May 16, 2002, co-assigned to Applied Materials. No. 6906], paragraphs 25-81 of which are hereby described to the extent that they are consistent with the claims and aspects claimed herein. Has been incorporated. Similarly, relative motion for surface-up polishing is provided between the substrate and the electrodes and / or pads.

  [0027] The process cell 200 is placed on a polishing platform such as a Reflexion® CMP system, a Mirra® CMP system, a Mirra® Mesa CMP system, which are Applied Materials in Santa Clara, California. It is commercially available from the company. Moreover, any system that allows electrochemical mechanical polishing using the methods or compositions described herein can be used to provide convenience.

Polishing composition and process
[0028] In one aspect, a polishing composition capable of planarizing a metal such as copper is provided. In general, the polishing composition comprises an acid-based electrolyte system, one or more chelating agents, one or more corrosion inhibitors, one or more inorganic acid salts or organic acid salts, and one type. And a polishing accelerator material selected from the group consisting of the above pH adjusting agent, pH of about 2 to about 10, abrasive particles, one or more oxidizing agents, and combinations thereof, and a solvent. The polishing compositions described herein contribute to improved polishing and effective removal rates of conductive materials such as copper during ECMP resulting in effective planarization of the substrate and a smooth surface after polishing. Conceivable.

  [0029] Although the polishing composition is particularly effective for removing copper, the polishing composition may be aluminum, platinum, tungsten, titanium, titanium nitride, tantalum, tantalum nitride, cobalt, gold, silver, and combinations thereof. It is considered that it is also used for removing other conductive materials. Other materials used to form conductive material features on the substrate surface include materials that form the barrier layer, for example, tantalum, tantalum nitride, titanium, titanium nitride are removed by the processes described herein. can do. Mechanical polishing, such as from contact with a polishing pad and / or abrasive, is used to improve the planarity and removal of the conductive material, and is carbon doped silicon oxide and doped or undoped It can also be used to remove conductive materials including silicon carbide.

  [0030] The polishing composition includes an acid-based electrolyte system to provide electrical conductivity. Suitable acid-based electrolyte systems include, for example, sulfuric acid-based electrolytes, phosphoric acid-based electrolytes, perchloric acid-based electrolytes, acetic acid-based electrolytes, and combinations thereof. Suitable acid electrolyte systems also include acid electrolytes such as phosphoric acid and sulfuric acid, and acid electrolyte derivatives including ammonium salts and potassium salts thereof. Acid-based electrolyte systems can also buffer the composition to maintain the desired pH level for processing the substrate.

[0031] Suitable acid-based electrolytes include phosphoric acid, potassium phosphate (K ₃ PO ₄ ), copper phosphate, ammonium dihydrogen phosphate (NH ₄ H ₂ PO ₄ ), diammonium hydrogen phosphate ((NH ₄ ) A compound having a phosphate group (PO ₄ ³⁻ ) such as HPO ₄ ) and a sulfate group (SO ₄ ³ ) such as sulfuric acid, ammonium hydrogen sulfate ((NH ₄ ) ₂ HSO ₄ ), copper sulfate or a combination thereof. ^-) it contains a compound having a. The present invention also contemplates that conventional known and unknown electrolytes can be used to form the compositions described herein using the processes described herein. .

  [0032] Alternatively, the acid-based electrolyte system provides about 1-30 wt% (wt.%) Or volume% of the composition to provide conductivity suitable for performing the processes described herein. (vol%) amount can be supplied. For example, dihydrogen phosphate and / or diammonium hydrogen phosphate can be present in the composition in an amount of about 15-25 weight or volume percent of the solution. Phosphoric acid can be present at a concentration of up to 30 wt.%, Such as from about 2 wt.% To about 6 wt.%.

  [0033] In any of the embodiments described herein, the chelating agent can bind to a conductive material, such as copper ions, to increase the removal rate of the metal material and to process the substrate. It can be used to buffer or adjust the polishing composition to maintain a desired pH level.

  [0034] The one or more chelating agents are selected from amine groups, amide groups, carboxylate groups, dicarboxylate groups, tricarboxylate groups, hydroxyl groups, mixtures of hydroxyl groups and carboxylate groups, and combinations thereof. In addition, compounds having one or more functional groups can be included. The one or more chelating agents can also include salts of the chelating agents described herein. The removal metal material, such as copper, may be in any oxidation state such as 0, 1 or 2 before, during and after bonding with the functional group. The functional group can bind the metal material generated on the substrate surface during processing and remove the metal material from the substrate surface.

  [0035] The polishing composition can include one or more chelating agents at a concentration of about 0.1% to 15% by volume or weight, such as about 0.1% to about 4% by volume or weight. For example, about 2 volumes or weight percent ethylenediamine can be used as a chelating agent.

  [0036] Examples of suitable chelating agents include one or more amine or amide functional groups such as ethylenediamine, diethylenetriamine, diethylenetriamine derivatives, hexadiamine, amino acids, ethylenediaminetetraacetic acid, methylformamide, or combinations thereof. The compound which has is mentioned.

  [0037] Examples of suitable chelating agents having one or more carboxyl groups include citric acid, tartaric acid, succinic acid, succinic acid, and combinations thereof. Other suitable acids having one or more carboxylate groups include acetic acid, adipic acid, butyric acid, capric acid, caproic acid, caprylic acid, glutaric acid, glycolic acid, formic acid, fumaric acid, lactic acid, lauric acid, apple Acids, maleic acid, malonic acid, myristic acid, palmitic acid, phthalic acid, propionic acid, pyruvic acid, stearic acid, valeric acid and combinations thereof are included.

  [0038] In any of the embodiments described herein, the inorganic acid salt or organic acid salt can be performed as a chelating agent. The polishing composition comprises one abnormal inorganic acid salt or organic acid salt at a concentration of about 0.1% to about 15% by volume or weight, for example, 0.1% to 6% or weight% of the composition. Can do. For example, about 2 volumes or weight percent of ammonium citrate can be used in the polishing composition.

  [0039] Examples of suitable inorganic or organic acid salts include ammonium oxalate, ammonium citrate, ammonium succinate, monobasic potassium citrate, dibasic potassium citrate, tribasic potassium citrate, It includes ammonium and potassium salts of organic acids such as potassium tartrate, ammonium tartrate, potassium succinate, potassium oxalate, and combinations thereof. Furthermore, ammonium salts and potassium salts of carboxylic acids described herein can also be used as organic acid salts of the compositions described herein.

  [0040] In any of the embodiments described herein, the corrosion inhibitor reduces or minimizes the chemical interaction between the material deposited on the substrate surface and the surrounding electrolyte. By forming the material layer, oxidation or corrosion of the metal surface can be prevented. The material layer formed by the corrosion inhibitor insulates the surface from the surrounding electrolyte and thus suppresses or minimizes electrochemical flow from the substrate surface to limit electrochemical deposition and / or dissolution. The polishing composition can comprise about 0.001% and about 5.0% by weight of organic compounds having azole groups, for example, about 0.2% to about 0.4% by weight.

  [0041] The one or more corrosion inhibitors can include an organic compound having one or more azole groups. Examples of organic compounds having an azole group include benzotriazole, mercaptobenzotriazole, 5-methyl-1-benzotriazole, and combinations thereof. Other suitable corrosion inhibitors include film formers that are cyclic compounds such as imidazole, benzimidazole, triazole, and combinations thereof. Benzotriazole, imidazole, benzimidazole, and triazole derivatives substituted with a hydroxy group, amino group, imino group, carboxy group, mercapto group, nitro group, and alkyl group can be used as a corrosion inhibitor. Other corrosion inhibitors include urea and thiourea among various others.

  [0042] Alternatively, the polymerization inhibitor, as a non-limiting example, polyalkylaryl ether phosphate or ammonium nonylphenol ethoxylate sulfate may be in an amount of about 0.002% to 1.0% in place of or with an azole-containing corrosion inhibitor. Can be used.

  [0043] The one or more pH modifiers contribute to the pH adjustment of the polishing composition. A preferred pH of the polishing composition may be about 2 to about 10, for example, a pH of about 4 to about 6. The polishing composition comprises up to about 70 wt.% Of one or more pH modifiers, such as from about 0.2% to about 25 volume or weight percent of one or more pH modifiers. Can be included. Different compounds can give different pH levels for a given concentration. For example, the composition can include a base such as about 0.1% to about 10% by volume potassium hydroxide, ammonium hydroxide, or combinations thereof to provide a preferred pH level.

  [0044] The one or more pH modifiers are carboxylic acids such as organic acids such as phosphoric acid-containing components including acetic acid, citric acid, oxalic acid, phosphoric acid, ammonium phosphate, potassium phosphate, or combinations thereof. Inorganic acids such as sulfuric acid, nitric acid, and strong acids including combinations thereof, which can be a combination thereof, can also be used in the polishing composition.

  [0045] The one or more pH modifiers can also include a base, such as potassium hydroxide, ammonium hydroxide, or a combination thereof. The amount of base used in the polishing composition is typically that amount necessary to adjust the pH of the composition to a desired level of about 2 to about 10.

  [0046] Alternatively, the polishing composition can comprise a base and a compound selected from the group consisting of acetic acid, citric acid, oxalic acid, phosphoric acid, ammonium phosphate, potassium phosphate, or combinations thereof. In a composition comprising both a base and a compound selected from the group identified herein, the composition comprises about 0.1% to 10% base and about 0.2% to about 25% by volume or weight%. A compound selected from the group consisting of acetic acid, citric acid, oxalic acid, phosphoric acid, ammonium phosphate, potassium phosphate, or a combination thereof may be provided.

  [0047] The polishing composition includes one or more polishing promoting materials including abrasive particles, one or more oxidizing agents, and combinations thereof.

  [0048] The abrasive particles can be used to improve the removal rate or removal of the conductive material from the substrate surface during polishing. The abrasive particles may comprise up to about 35 wt.% Polishing composition during processing. A concentration of abrasive particles of about 0.001 wt.% To 5 wt.% Can be used in the polishing composition.

  [0049] Suitable abrasive particles include an inorganic abrasive, a polymeric abrasive, or a combination thereof. Inorganic abrasive particles that can be used in the electrolyte include silica, alumina, zirconium oxide, titanium oxide, cerium oxide, germania, or any other abrasive of a known or unknown metal oxide, with an average size. About 20 nm to about 1000 nm. In general, suitable inorganic abrasives have a Mohs hardness of 6 or greater, and the present invention contemplates the use of lower Mohs abrasives in the polishing composition.

  [0050] The polymer abrasives described herein can also be referred to as "organic polymer particle abrasives", "organic abrasives" or "organic particles". The polymer abrasive may comprise a polymer abrasive material. Examples of polymer abrasives include polymethyl methacrylate, polymethyl acrylate, polystyrene, polymethacrylonitrile, or combinations thereof.

  [0051] The Shore hardness of the polymeric abrasive is about 60 to about 80, and can be varied to a greater or lesser hardness. The polymer abrasive may also be softer than the inorganic particles described herein, which reduces the friction between the object to be polished and the substrate, resulting in scratches and other scratches compared to the inorganic particles. There will be a reduction in the number and severity of surface defects. The polymer abrasive is also harder than the material used in any polishing pad material that has improved polishing performance compared to the polishing pad material alone.

  [0052] The hardness of the polymeric abrasive can be varied by controlling the degree of polymer crosslinking in the abrasive. For example, a higher degree of crosslinking increases the hardness of the polymer and thus provides an abrasive. The average diameter of the polymeric abrasive is typically formed as spherical beads of about 1 micron to about 20 microns or less.

  [0053] The polymeric abrasive has an affinity for, ie, can bind, a functional group, eg, one or more functional groups, to the conductive material or conductive material ions that are removed from the substrate or composition. Can be modified to help remove conductive material from the surface of the substrate during processing. For example, if copper is removed during the polishing process, the organic polymer particles bind to the removed copper, for example, in addition to or in place of a chemically active agent in the composition, such as a chelating agent. It can be modified to have amine groups, carboxylate groups, pyridine groups, hydroxide groups, ligands with high affinity for copper, or combinations thereof used as articles. The metal material to be removed, such as copper, can be in any oxidation state such as 0, 1, 2 before, during and after bonding with the functional group. The functional group can bind the metal material generated on the substrate surface during processing and remove the metal material from the substrate surface.

  [0054] In addition, polymeric abrasives have desirable chemical properties. For example, polymer abrasives are stable over a wide pH range and do not attempt to assemble together. This allows the polymer abrasive to be used with reduced or no surfactant or dispersant in the composition.

  [0055] Alternatively, inorganic particles coated with the polymeric materials described herein can also be used with the polishing composition. The abrasive used in the composition may be a combination of a polymeric abrasive, an inorganic abrasive, and a polymer-coated inorganic abrasive, depending on the desired polishing performance and results.

[0056] One or more oxidizing agents may be used herein to improve the removal or removal rate of the conductive material from the substrate surface. As used herein, an oxidant is generally a substance that receives electrons from one or more layers of a substrate being polished and oxidizes the material thereon for more effective removal of the material. For example, an oxidizing agent can be used to oxidize the metal layer to the corresponding oxide or hydroxide, for example, copper to copper oxide. Oxidized existing copper containing Cu ¹⁺ can be further oxidized to a higher oxidation state like Cu ²⁺ ions. This can then be reacted with a chelating agent.

  [0057] The oxidizing agent may be present in the polishing composition in an amount ranging from about 0.01% to about 90% by volume or weight percent, such as from about 0.1% to about 20% volume or weight percent. In embodiments of the polishing composition, about 0.1% to about 15% hydrogen peroxide is present in the polishing composition.

  [0058] Examples of suitable oxidizing agents include peroxy compounds, such as hydrogen peroxide and urea hydrogen peroxide, carbonates, and, for example, alkyl peroxides, cyclic or aryl peroxides, benzoyl peroxide, peracetic acid, or di- Examples include compounds that can be dissociated by hydroxy groups such as adducts including organic peroxides including t-butyl peroxide. Sulfates and sulfate derivatives such as monopersulfate and dipersulfate can also be used including, for example, ammonium peroxydisulfate, potassium peroxydisulfate, ammonium persulfate, or potassium persulfate. Salts of peroxide compounds such as sodium percarbonate and sodium peroxide are also used.

  [0059] Oxidizing agents can also be inorganic compounds or compounds containing elements in the highest oxidation state. Examples of inorganic compounds or compounds containing elements in the highest oxidation state include periodic acid, periodate, perbromate, perbromate, perchloric acid, perchlorate, perboric acid, nitrate (But not limited to) perborates or permanganates (such as cerium nitrate, iron nitrate, ammonium nitrate). Other oxidizing agents include bromate, chlorate, chromate, iodate, iodate, or cerium (IV) compounds such as cerium ammonium nitrate.

  [0060] The balance of the polishing composition, ie, the remainder, is water, preferably deionized water, and a solvent such as a polar solvent including an organic solvent such as an alcohol or glycol.

  [0061] Furthermore, by controlling the amount and type of components of the polishing composition, such as corrosion inhibitors and oxidants, it may be possible to adjust the desired removal rate of the process. For example, a small amount of corrosion inhibitor will increase the removal rate compared to a composition with a high corrosion prevention rate, and a small amount of oxidant will have a slower removal rate than a composition with a high oxidant composition. .

  [0062] Examples of polishing compositions described herein include about 2% by volume ethylene diamine, about 2% by weight ammonium citrate, about 0.3% by weight benzotriazole, about 0.1% to About 3% by volume or weight%, for example about 0.45% hydrogen peroxide, and / or about 0.01% to 1% by weight, eg 0.15% by weight abrasive particles, and about 6% by volume. Contains phosphoric acid. The composition has a pH of about 5, and can be achieved, for example, by a composition further comprising potassium hydroxide to adjust the pH to a preferred range. The balance of the polishing composition is deionized water.

  [0063] Alternatively, the polishing composition comprises an electrolyte additive comprising an inhibitor, accelerator, smoothing agent, brightener, stabilizer, and stripping agent that improves the effectiveness of the polishing composition in polishing the substrate surface. Further, it can be included. For example, certain additives can reduce the ionization rate of metal atoms, thereby preventing the dissolution process. In contrast, other additives can provide a finished glossy substrate surface. Additives can be present in the polishing composition at a concentration of up to about 15 weight or volume percent and can vary based on the desired result after polishing.

  [0064] For example, one or more surfactants can be used in the polishing composition. Surfactants increase the dissolution or solubility of materials such as metals and metal ions or by-products generated during processing, reduce any potential aggregation of abrasive particles in the polishing composition, It can be used to improve the chemical stability of the components of the polishing composition and reduce degradation. The one or more surfactants can comprise a concentration of about 0.001% to about 10% of the polishing composition. A surfactant concentration of about 0.01% to about 2%, such as about 0.1% to about 1 volume or weight percent, can be used in one embodiment of the polishing composition.

  [0065] The one or more surfactants are more than one, such as a nonionic surfactant, or an anionic surfactant, a cationic surfactant, an amphoteric surfactant, or a zwitterionic surfactant. An ionic surfactant including an ionic surfactant having an ionic functional group can be included. The dispersant is considered to be a surfactant as the surfactant is used herein. Compositions containing polymer abrasives are stable over a wide pH range and do not fluoresce together. This allows the polymer abrasive to be used with little or no surfactant in the composition or no dispersant.

  [0066] Other examples of additives include one or more smoothing agents as broadly defined herein as additives that suppress dissolution current on the substrate surface. The smoothing agent attaches to the conductive material, suppresses the dissolution current by blocking the electrochemical reaction between the electrode and the conductive material, and / or forms a depolarizer that limits the electrochemical reaction. A leveling agent concentration of about 0.005% to about 10% by volume or weight percent, for example, about 0.05% to 2% by volume or weight percent can be used.

  [0067] Smoothing agents include, but are not limited to, polyethylene glycol and polyethylene glycol derivatives. Other leveling agents that can be used in the processes described herein include polyethyleneimine, polyglycine, 2-amino-1-naphthalenesulfonic acid, 3-amino-1-propanesulfonic acid, 4-amino. Any used in electroplating techniques such as polyamines, polyamides, polyimides, including toluene-2-sulfonic acid are included.

  [0068] A suppressor, such as an electrical resistance additive that reduces the conductivity of the polishing composition, may be added to the composition in an amount of from about 0.005% to about 2 volume or weight percent of the composition. Suppressors include polyacrylamide, polyacrylic acid polymer, polycarboxylate polymer, coconut diethanolamide, olein diethanolamide, ethanolamide derivatives, or combinations thereof.

  [0069] The one or more stabilizers may be present in an amount sufficient to provide a measurable improvement in the stability of the composition. The one or more stabilizers can be present in an amount ranging from about 100 ppm to about 5.0 weight percent (wt.%). Non-limiting examples of preferred stabilizers include aminotri (methylenephosphonic) acid, 1-hydroxyethylidene-4-diphosphonic acid, hexamethylenediaminetetramethylenephosphoric acid, or diethylenetetraminepentamethylenephosphonic acid, or a derivative salt thereof. However, it is not limited to these.

  [0070] Accelerators are other examples of additives that can be included in the polishing composition. The promoter increases the electrochemical reaction of the metal disposed on the substrate surface to increase metal removal. The composition can include one or more accelerators at a concentration of about 0.1 to about 1 volume or weight percent, such as about 0.25 to about 0.8 volume or weight percent. Accelerators can include sulfur-containing compounds such as sulfite or disulfate.

  [0071] Examples of additives to the polishing composition are further described more fully in US patent application Ser. No. 10 / 141,459, filed May 7, 2002, the disclosure of which is claimed herein. To the extent not inconsistent with the disclosed embodiments and disclosures.

  [0072] Substrates treated with the polishing compositions described herein are improved with fewer surface defects such as dishing, erosion (removal of dielectric material surrounding metal features), and scratches. It has been observed that surface finishes including flat surfaces have been improved.

Power supply and processing:
[0073] Power can be applied to a substrate having a conductive material layer formed thereon in a process apparatus, such as the vessel 200, by applying a potential difference between the electrode and the substrate to remove the conductive material. it can.

  [0074] In an example of a polishing process, the substrate 208 is placed in a polishing head 202 that is used in a planarization process as shown in FIG. The polishing head 202 provides a polishing pad assembly to apply pressure to the substrate surface to be electrochemically and mechanically polished in the range of about 0.01 psi to about 1 psi, such as about 0.1 psi to about 0.5 psi. 222 can be contacted.

[0075] The polishing pad assembly 222 is disposed within a basin that includes an electrolyte described herein. The substrate 208 is exposed to the polishing composition and is in electrical contact with the conductive pad 203. The potential difference from the power source 224 is then applied between the substrate 208 and the conductive pad 203. The potential difference is typically up to about 300 mm, for example, at a current density of up to 100 milliamps / cm ² to include processing a substrate of about 0.01 to about 40 milliamps / cm ² for a 200 mm substrate. The surface is subjected to anodic dissolution of the conductive material.

  [0076] The potential difference may vary in power and supply depending on the user's requirement to remove material from the substrate surface. The potential difference is also provided by an electrical pulse modulation technique, which is co-pending US patent application Ser. No. 6,379, filed Apr. 22, 2002, entitled “Method and Apparatus for Electrochemical Mechanical Planarization”. As described in No. 223, a constant current density or voltage is applied to the first time period, and then a constant reverse current density or voltage is applied to the second time period. The two steps are repeated, the disclosure of which is hereby incorporated to the extent consistent with the aspects and disclosure claimed herein.

  [0077] The potential difference was generally exposed to the polishing composition to remove the copper-containing material at a rate of about 15,000 angstroms / minute, such as from about 100 angstroms / minute to 15,000 angstroms / minute. Given to the substrate surface. In one embodiment of the invention where the copper material being removed is less than 5,000 angstroms thick, the voltage is provided to provide a removal rate between about 100 angstroms / minute and about 5,000 angstroms / minute. be able to.

  [0078] The substrate is typically exposed to the polishing composition and power supply for a time sufficient to remove the polishing composition and at least some or all of the material disposed thereon.

  [0079] Although the exact mechanism for planarizing the substrate is unknown, the planarization process is believed to be as follows. Passivating layer that chemically and / or electrically insulates the surface of the substrate is a corrosion inhibitor, or other material that can form a passivating film or insulating film with the material to be removed. For example, by exposure to an oxidant capable of forming an oxide layer and / or a chelating agent capable of forming a chelating layer. The potential difference is applied to remove the conductive material or to improve the removal of the conductive material, such as a copper-containing material, from the substrate surface by anodic dissolution.

  [0080] The passivating layer insulates or suppresses the current for anodic dissolution, and mechanical polishing is performed from the contact area between the transmissive disk and the substrate, eg, excessive deposition or topography of the underlying layer. Is provided between the substrate and the transmissive disc to remove the passivation layer from the protrusions formed on the substrate surface and to expose the underlying copper-containing material. The passivation layer is held in a minimal or non-contact area such as a groove or valley on the substrate surface. The exposed copper-containing material can then be electrically connected to the electrolyte and removed by anodic dissolution.

  [0081] Selective removal of the passivating layer from the protrusions by contact with the object to be polished, for example, the conductive pad 203 under a given potential difference while holding the passivating layer in the trough, The excess copper-containing material can be removed from the non-passivated portion of the substrate surface in connection with the increase in the thickness and / or the removal of the conductive material under the passivation layer. The increased dissolution and removal of the copper-containing material without the passivation layer formed thereon allows for an increased reduction in protrusions formed on the substrate surface compared to the valleys formed thereon. As a result, planarization of the substrate surface is promoted.

  [0082] Furthermore, removing material by polishing and anodic dissolution allows the substrate surface to be planarized at a lower polishing pressure (ie, about 2 psi or less) than conventional polishing. Lower polishing pressures flatten the substrate surface sensitive to contact pressure between the substrate and the polishing pad so as to polish low-k dielectric materials, with this process reduced or minimal deformation and defect formation from polishing. Corresponds to smaller shear and friction forces that make it suitable for use. Furthermore, smaller shear and friction forces were observed to reduce or minimize topography defect formation such as dishing and scratching during polishing.

  [0083] The following non-limiting examples are presented to more specifically illustrate embodiments of the present invention. However, the examples are not intended to be exhaustive or to limit the scope of the invention described herein.

Example 1:
[0084] Copper plated wafers were polished and planarized using the following polishing composition in a cell modified for the Reflection® system available from Applied Materials, Inc., Santa Clara, California.
About 6% by volume phosphoric acid;
About 2% by volume of ethylenediamine;
About 2% by weight ammonium citrate;
About 0.3% by weight of benzotriazole;
Potassium hydroxide which provides a pH of about 5 from about 2% to about 6%;
About 0.45% by volume of hydrogen peroxide;
Deionized water.

Example 2:
[0085] The copper plated wafer was polished and planarized using the following polishing composition in a cell modified for the Reflection® system available from Applied Materials, Inc., Santa Clara, California.
About 6% by volume phosphoric acid;
About 2% by volume of ethylenediamine;
About 2% by weight ammonium citrate;
About 0.3% by weight of benzotriazole;
Potassium hydroxide which provides a pH of about 5 from about 2% to about 6%;
About 0.45% by volume of hydrogen peroxide;
About 0.15 wt% silica (SiO ₂ ) abrasive particles;
Deionized water.

Example 3:
[0086] The copper plated was polished and planarized using the following polishing composition in a cell modified for the Reflection® system available from Applied Materials, Inc., Santa Clara, California.
About 6% by volume phosphoric acid;
About 2% by volume of ethylenediamine;
About 2% by weight ammonium citrate;
About 0.3% by weight of benzotriazole;
Potassium hydroxide which provides a pH of about 2% to about 6% of about 6;
About 0.1% by weight silica (SiO ₂ ) abrasive particles;
Deionized water.

  [0087] While the above is directed to embodiments of the invention, many more embodiments of the invention can be devised without departing from the basic scope thereof, which scope is determined by the following claims.

1 is a cross-sectional view of one embodiment of a polishing process station.

Explanation of symbols

DESCRIPTION OF SYMBOLS 200 ... Process cell, 202 ... Polishing head, 203 ... Conductive pad, 204 ... Basin, 206 ... Base, 207 ... Backing, 208 ... Substrate, 209 ... Electrode, 210 ... Drive system, 214 ... Housing, 216 ... Bladder, 218 ... Port, 220 ... Valve, 222 ... Pad assembly, 223A, B ... Electric wire, 224 ... Power supply, 226 ... Slip ring, 228 ... Catch basin, 230 ... Outlet, 232 ... Distribution system, 234 ... Bearing, 236 ... Drive system, 238 ... retaining ring, 242 ... polishing composition supply source, 244 ... bottom, 246 ... sidewall, 250 ... conditioning device, 252 ... arm, 256 ... shaft, 258 ... conditioning element.

Claims (35)

A composition for removing at least a conductive material from a substrate surface,
An acid-based electrolyte system;
One or more chelating agents;
One or more corrosion inhibitors;
One or more inorganic acid salts or organic acid salts;
One or more pH modifiers providing about 2 to about 10 pH;
A polishing promoting material selected from abrasive particles, one or more oxidizing agents, and combinations thereof;
With a solvent;
Comprising the composition.   The acid-based electrolyte system is selected from the group of phosphoric acid-based electrolytes, sulfuric acid-based electrolytes, perchloric acid-based electrolytes, acetic acid-based electrolytes, and combinations thereof. Composition.   A compound in which one or more of the chelating agents have one or more functional groups selected from the group consisting of an amine group, an amide group, a carboxylate group, a dicarboxylate group, a tricarboxylate group, and combinations thereof; A composition according to claim 1 comprising.   One or more of the chelating agents are ethylenediamine, hexadiamine, amino acid, ethylenediaminetetraacetic acid, methylformamide, citric acid, tartaric acid, succinic acid, oxalic acid, acetic acid, adipic acid, butyric acid, capric acid, caproic acid, caprylic acid , Glutaric acid, glycolic acid, formic acid, fumaric acid, lactic acid, lauric acid, malic acid, maleic acid, malonic acid, myristic acid, palmitic acid, phthalic acid, propionic acid, pyruvic acid, stearic acid, valeric acid, and combinations thereof The composition according to claim 3, which is selected from the group consisting of:   The composition of claim 1, wherein the one or more corrosion inhibitors have one or more azole groups.   Benzotriazole, imidazole, wherein one or more corrosion inhibitors are substituted with benzotriazole, imidazole, benzimidazole, triazole, and hydroxy, amino, imino, carboxy, mercapto, nitro, alkyl groups 6. The composition of claim 5, selected from the group consisting of benzimidazole, triazole derivatives, and combinations thereof.   The composition of claim 1, wherein the one or more inorganic or organic salts comprise an ammonium salt of an organic acid, a potassium salt of an organic acid, or a combination thereof.   One or more of the inorganic or organic salts may be ammonium oxalate, ammonium citrate, ammonium succinate, monobasic potassium citrate, dibasic potassium citrate, tribasic potassium citrate, potassium tartrate, ammonium tartrate 8. The composition of claim 7, selected from the group of: potassium succinate, potassium oxalate, and combinations thereof. One or more acids selected from the group consisting of organic carboxylic acids, strong inorganic acids, and combinations thereof, wherein the one or more pH modifiers;
Phosphate-containing components;
The composition of claim 1 comprising one or more bases selected from the group of potassium hydroxide, ammonium hydroxide, and combinations thereof; or combinations thereof.   The composition of claim 1, wherein the abrasive comprises an inorganic abrasive, a polymeric abrasive, or a combination thereof.   The one or more oxidizing agents are selected from the group of peroxy compounds, salts of peroxy compounds, organic peroxides, sulfates, sulfate derivatives, compounds containing elements in the highest oxidation state, and combinations thereof. The composition as described. From about 1% to about 30% by weight (wt.%) Of the acid-based electrolyte system with respect to the total composition volume;
From about 0.1% to about 15% by volume or weight percent of one or more of the chelating agents;
From about 0.01% to about 1.0 volume or weight percent of one or more of the corrosion inhibitors;
From about 0.1% to about 15% by volume or weight percent of one or more of the inorganic or organic acid salts;
From about 0.1% to about 25% by volume or weight percent of the pH modifier;
From about 0.001% to about 30% by weight abrasive particles;
With remaining solvent;
The composition of claim 1 comprising:   13. The composition of claim 12, further comprising about 0.1% to about 25 volume or weight percent of one or more oxidizers. About 1% to about 30% by weight of the acid-based electrolyte system with respect to the total composition volume;
From about 0.1% to about 15% by volume or weight percent of one or more of the chelating agents;
From about 0.001% to about 5.0 volume or weight percent of one or more of the corrosion inhibitors;
From about 0.1% to about 15% by volume or weight percent of one or more of the inorganic or organic acid salts;
From about 0.1% to about 25% volume or weight of the pH modifier;
From about 0.1% to about 25% by volume or weight percent oxidizing agent;
With remaining solvent;
The composition of claim 1 comprising: The composition comprises about 6% by volume phosphoric acid;
About 2% by volume ethylenediamine;
About 0.3% by weight of benzotriazole;
About 2% by weight of ammonium citrate;
Potassium hydroxide to obtain about 2 to about 6 volume percent pH about 5;
From about 0.1 to about 0.15% by weight of silica abrasive;
With deionized water;
The composition of claim 1 comprising:   16. The composition of claim 15, further comprising about 0.45% by volume hydrogen peroxide. The composition comprises about 6% by volume phosphoric acid;
About 2% by volume ethylenediamine;
About 0.3% by weight of benzotriazole;
About 2% by weight of ammonium citrate;
About 2% to about 6% by volume of potassium hydroxide providing a pH of about 5;
About 0.45% by weight of hydrogen peroxide;
With deionized water;
The composition of claim 1 comprising: A method of processing a substrate, comprising:
Disposing a substrate having a conductive material layer formed thereon in a process apparatus comprising a first electrode and a second electrode, wherein the substrate is in electrical contact with the second electrode; Steps and;
Supplying a polishing composition between the first electrode and the substrate, the polishing composition comprising an acid-based electrolyte system;
One or more chelating agents;
One or more corrosion inhibitors;
One or more inorganic acid salts or organic acid salts;
One or more pH modifiers providing about 2 to about 10 pH;
A polishing promoting material selected from the group of abrasive particles, one or more oxidizing agents, and combinations thereof;
With a solvent;
Said step comprising:
Providing a potential difference between the first electrode and the second electrode;
Removing the conductive material from the conductive material layer. 19. The method of claim 18, wherein the potential difference is applied to the substrate to initiate anodic dissolution at a current density of about 0.01 milliamps / cm < ² > to about 100 milliamps / cm < ² >.   19. The acid-based electrolyte system is selected from the group of phosphoric acid-based electrolyte, sulfuric acid-based electrolyte, perchloric acid-based electrolyte, acetic acid-based electrolyte, and combinations thereof. Method.   A compound in which one or more of the chelating agents have one or more functional groups selected from the group consisting of an amine group, an amide group, a carboxylate group, a dicarboxylate group, a tricarboxylate group, and combinations thereof; 19. The method of claim 18, comprising.   One or more of the chelating agents are ethylenediamine, hexadiamine, amino acid, ethylenediaminetetraacetic acid, methylformamide, citric acid, tartaric acid, succinic acid, oxalic acid, acetic acid, adipic acid, butyric acid, capric acid, caproic acid, caprylic acid , Glutaric acid, glycolic acid, formic acid, fumaric acid, lactic acid, lauric acid, malic acid, maleic acid, malonic acid, myristic acid, palmitic acid, phthalic acid, propionic acid, pyruvic acid, stearic acid, valeric acid, and combinations thereof The method of claim 21, wherein the method is selected from the group consisting of:   The method of claim 18, wherein the one or more corrosion inhibitors have one or more azole groups.   Benzotriazole, imidazole, wherein one or more corrosion inhibitors are substituted with benzotriazole, imidazole, benzimidazole, triazole, and hydroxy, amino, imino, carboxy, mercapto, nitro, alkyl groups 24. The method of claim 23, selected from the group consisting of benzimidazole, triazole derivatives, and combinations thereof.   The method of claim 18, wherein the one or more inorganic or organic salts comprise an ammonium salt of an organic acid, a potassium salt of an organic acid, or a combination thereof.   One or more of the inorganic or organic salts may be ammonium oxalate, ammonium citrate, ammonium succinate, monobasic potassium citrate, dibasic potassium citrate, tribasic potassium citrate, potassium tartrate, ammonium tartrate 26. The method of claim 25, selected from the group of: potassium succinate, potassium oxalate, and combinations thereof. One or more acids selected from the group consisting of organic carboxylic acids, strong inorganic acids, and combinations thereof, wherein the one or more pH modifiers;
Phosphate-containing components;
19. The method of claim 18, comprising one or more bases selected from the group of potassium hydroxide, ammonium hydroxide, and combinations thereof; or combinations thereof.   The method of claim 18, wherein the abrasive comprises an inorganic abrasive, a polymeric abrasive, or a combination thereof.   19. The one or more oxidizing agents are selected from the group of peroxy compounds, salts of peroxy compounds, organic peroxides, sulfates, sulfate derivatives, compounds containing elements in the highest oxidation state, combinations thereof. the method of. From about 1% to about 30% by weight (wt.%) Of the acid-based electrolyte system with respect to the total composition volume;
From about 0.1% to about 15% by volume or weight percent of one or more of the chelating agents;
From about 0.01% to about 1.0 volume or weight percent of one or more of the corrosion inhibitors;
From about 0.1% to about 15% by volume or weight percent of one or more of the inorganic or organic acid salts;
From about 0.1% to about 25% by volume or weight percent of the pH modifier;
From about 0.01% to about 30% by weight abrasive particles;
With remaining solvent;
19. The composition of claim 18 comprising:   32. The composition of claim 30, further comprising from about 0.1% to about 25 volume or weight percent of one or more of the oxidizer. About 1% to about 30% by weight of the acid-based electrolyte system with respect to the total composition volume;
From about 0.1% to about 15% by volume or weight percent of one or more of the chelating agents;
From about 0.01% to about 1.0 volume or weight percent of one or more of the corrosion inhibitors;
From about 0.1% to about 15% by volume or weight percent of one or more of the inorganic or organic acid salts;
From about 0.1% to about 25% by volume or weight percent of the pH modifier;
From about 0.1% to about 25% by volume or weight percent oxidizing agent;
With remaining solvent;
The method of claim 18 comprising: The composition comprises about 6% by volume phosphoric acid;
About 2% by volume ethylenediamine;
About 0.3% by weight of benzotriazole;
About 2% by weight of ammonium citrate;
Potassium hydroxide to obtain about 2 to about 6 volume percent pH about 5;
From about 0.1 to about 0.15% by weight of silica abrasive;
With deionized water;
The method of claim 18 comprising:   34. The method of claim 33, further comprising about 0.45% by volume hydrogen peroxide. The composition comprises about 6% by volume phosphoric acid;
About 2% by volume ethylenediamine;
About 0.3% by weight of benzotriazole;
About 2% by weight of ammonium citrate;
Potassium hydroxide providing a pH of about 2% to about 6% by volume of about 5;
About 0.45% by volume of hydrogen peroxide;
With deionized water;
The method of claim 18 comprising:

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