US3668131A - Dissolution of metal with acidified hydrogen peroxide solutions - Google Patents

Dissolution of metal with acidified hydrogen peroxide solutions Download PDF

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US3668131A
US3668131A US751388A US3668131DA US3668131A US 3668131 A US3668131 A US 3668131A US 751388 A US751388 A US 751388A US 3668131D A US3668131D A US 3668131DA US 3668131 A US3668131 A US 3668131A
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additive
hydrogen peroxide
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Russell S Banush
Donald P Hagerty
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Henley Group Inc
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Allied Chemical Corp
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Assigned to HENLEY GROUP, INC., THE, 11255 NORTH TORREY PINES RD, LA JOLLA, CA A CORP. OF DE reassignment HENLEY GROUP, INC., THE, 11255 NORTH TORREY PINES RD, LA JOLLA, CA A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ALLIED CORPORATION
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Assigned to WELLS FARGO BANK NATIONAL ASSOCIATION reassignment WELLS FARGO BANK NATIONAL ASSOCIATION SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GENERAL CHEMICAL CORPORATION, HENLEY MANUFACTURING HOLDING COMPANY, INC., PRESTOLITE WIRE CORPORATION, PRINTING DEVELOPMENTS, INC., SEMI-ALLOYS, INC., TOLEDO STAMPING & MANUFACTURING COMPANY
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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F1/00—Etching metallic material by chemical means
    • C23F1/10—Etching compositions
    • C23F1/14—Aqueous compositions
    • C23F1/16—Acidic compositions
    • C23F1/18—Acidic compositions for etching copper or alloys thereof
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F1/00—Etching metallic material by chemical means
    • C23F1/10—Etching compositions
    • C23F1/14—Aqueous compositions
    • C23F1/16—Acidic compositions

Definitions

  • Dissolution or etching of metals in the manufacture of printed circuits is not a simple matter and involves several considerations if it is to be a practical success. Among the more important considerations are rate of attack of the etchant, control of the etchant, stability and efficiency of the etchant, time and temperature conditions, effect of the etchant on the materials forming the printed circuit board, and efiect on the equipment and masking material employed in the etching process.
  • the disposition of the spent ferric chloride etchant solution containing both iron and copper has become a problem, largely because of the disposal of the waste liquor and difficulty in recovering copper therefrom which is, of course, desirable from a cost standpoint.
  • Other copper etchants have therefore been sought with the result that aqueous solutions of ammonium persulfate have been adopted by some users.
  • This etchant permits electrolytic recovery of copper from the spent etchant solution and eliminates the problem of disposing of metal containing waste liquors.
  • ammonium persulfate as an etchant is a premium material because of its low etching capacity and is subject to other drawbacks which have lefi considerable room for improvement in the provision of an etchant for copper.
  • aqueous hydrogen peroxide As an etchant for copper, aqueous hydrogen peroxide is very attractive because of its relatively low cost and ability to recover copper electrolytically from a spent peroxide etchant solution.
  • the utilization of hydrogen peroxide for a constructive purpose in metal etching is subject to numerous problems and pitfalls. Basically, potentially useful solutions combining hydrogen peroxide and acid were found subject to great deficiencies by way of etch rates and capacity.
  • acidified hydrogen peroxide solutions have been developed whereby metal may be dissolved or etched for constructive purposes in a practical manner and at considerable savings over conventional etching solutions.
  • Such solutions may contain additives such as phenacetin, sulfathiazole and silver ions, water soluble salts and mixtures thereof and satisfy all requirements necessary to constitute new and improved etchants for even copper metal, including unexpectedly fast etch rates and high capacity.
  • additives such as phenacetin, sulfathiazole and silver ions, water soluble salts and mixtures thereof and satisfy all requirements necessary to constitute new and improved etchants for even copper metal, including unexpectedly fast etch rates and high capacity.
  • etchants are designed to be prepared from concentrates and after preparation are subject to a loss of maximum eflectiveness with the passage of time, typically a depreciation of percent over a period of l236 hours.
  • Etchants of improved capability of storage for extended periods of time after preparation without substantial depreciation and capable of dissolving large amounts of metal at fast rates are disclosed in our US. Pat. No. 3,407,141.
  • the acidified hydrogen peroxide solution of that application is catalyzed
  • urea and thiourea compounds which have been found to increase the capacity and rate of etching of acidified hydrogen peroxide solutions are the substituted urea and thiourea compounds of the formula:
  • X is a member selected from oxygen and sulfur and each of RR, R and R is a radical which may be selected from hydrogen and a hydrocarbon radical (aliphatic, straight or branched, cyclic or aromatic, saturated or unsaturated, substituted or unsubstituted) containing up to about 18 carbon atoms, preferably up to about 12 carbon atoms.
  • a hydrocarbon radical aliphatic, straight or branched, cyclic or aromatic, saturated or unsaturated, substituted or unsubstituted
  • Those urea and thiourea compounds suitable for use in the acidified hydrogen peroxide solutions of the present invention should be soluble in the solution to an extent of at least about 20, preferably at least about 50, parts per million.
  • Substituted hydrocarbon radicals may be employed so long as the substitutent group does not adversely affect the etch rate or the capacity of the etchant solutions.
  • each of the R groups are, for instance, an alkyl radical, e.g., methyl, ethyl, propyl, isopropyl, butyl, tertiary-butyl, hexyl and octyl; an alkenyl radical, e.g., ethenyl (vinyl), allyl, l-propenyl, 3-hexenyl and 4-octenyl; a cycloalkyl radical, e.g., cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and 4-methylcyclohexyl; and aryl radical, e.g., phenyl, p-tolyl, xylyl (dirnethylphenyl), chlorophenyl, alkoxyphenyl, naphthyl; an aralkyl radical, e.g., benzyl,
  • Acidified hydrogen peroxide solutions having further and markedly improved etch rates and capacity are provided by incorporating therein a combination of one or more of the above-indicated additives with a small amount of at least one additive selected from the group consisting of sulfathiazole, phenacetin and silver ions.
  • the acidified peroxide solutions of the present invention are effective in dissolving copper, and may be employed in accurate, controlled and highly efiicient etching of copper-clad laminates as in the manufacture of printed circuit boards.
  • the additives may be employed in relatively small amounts, thus as little as 20parts per million is capable of providing an etchant of improved capacity etch rate. However, increasing the amount of additive will further increase etch rate and capacity of the solution. Thus, about 50-2,000 parts of an additive is preferred, with about to l,000 parts per million being especially preferred. The upper limit is not critical and is primarily a matter of economics. Generally, amounts of additive above about 5,000 parts per million offer no added advantage and are less desirable from a process and economic standpoint.
  • the etchant may also contain one or more additives from the group of sulfathiazole, phenacetin, and silver ions.
  • additives from the group of sulfathiazole, phenacetin, and silver ions.
  • the preferred total amount of additives is between about 100 to ISO-1,500 parts per million, with between about 50-500 parts per million of each being employed.
  • acidified hydrogen peroxide solutions for etching copper should contain less than 2 parts per million total free chloride and bromide ions, preferably less than 1 part per million.
  • deionized water may be used to make up an etchant containing less than 2 parts per million of chloride and bromide ions.
  • ordinary water may be employed in rnake up to the etchant solution if accompanied by addition of suitable material capable of removing free chloride and bromide ions.
  • a small amount of water-soluble silver salt preferably silver nitrate, may be added to effect the removal of chloride and bromide ion.
  • the precipitated silver halide matter may remain in the acid-peroxide solution since it does not interfere with the etching process.
  • the addition of excess soluble silver salt will furnish free silver ions in the etchant and have a highly beneficial and catalytic effect upon etch rate and capacity.
  • sulfathiazole When sulfathiazole is employed in the etchant the presence of chloride and bromide ions is less deleterious, and no special precautions to remove them need be taken. While the reason for this is uncertain, it is evident that sulfathiazole functions not only to increase the etching capacity of peroxide solutions, but also to negate the adverse repressive effect of the chloride and bromide ion concentration on etch rate and capacity. Hence, the addition of sulfathiazole may permit use of ordinary tap water in preparation of the etchants. Salts yielding sulfathiazole may also be employed and are generally preferred because such compounds are more easily dissolved in the acid-peroxide solution.
  • the sodium salt of sulfathiazole is an example of preferred salt which may be added to the solutions.
  • sulfathiazole When employing sulfathiazole for this purpose in etchants prepared from ordinary tap water between about 150 and 250 parts per million is usually required to negate the adverse eflects of the free chloride and bromide ions in the water.
  • the capacity of sulfathiazole in overcoming the adverse effect of chloride and bromide ion is apparently not unlimited. Solutions containing the higher concentrations of these ions, say above about -30 parts per million, will require additional treatment to negate this effect of such ions, ds qnizati sr sit of a bls ilvsr salt.
  • the hydrogen peroxide concentration may vary over a fairly wide range. Etching of metal is desirably carried out in acidified peroxide solutions having a hydrogen peroxide concentration between about 2-12 percent. At solution concentrations less than about 2 percent by weight etch rates are impractically low and etching unsatisfactory. At concentrations above 12 percent by weight, it has been found that copper metal may be etched, but the dissolution of the etched copper ions in the etchant causes decomposition of the peroxide with the result that etching at such high concentrations is less economical. The best results are obtained in solutions having a peroxide concentration between about 2-10 percent.
  • the hydrogen peroxide solutions employed in the invention should therefore have an initial hydrogen peroxide concentration of at least about 4 percent in order to dissolve sufficient metal to be practical from an economic standpoint.
  • the etchant solution has initially a hydrogen peroxide concentration within the range of about 5-10 percent by weight.
  • Such hydrogen peroxide solutions are useful in etching a single large metal piece or a series of workpieces containing limited amounts of metal.
  • the etchant is capable of operating effectively at good etch rates after partial exhaustion and at high dissolved concentrations of metals including copper in amounts equivalent to at lest 9 ounces of copper per gallon and even substantially higher.
  • the acid concentration may also vary considerably, and it is desirable that the etchant solution have a hydrogen ion concentration from about 0.45 to about 5.5 grams per liter, preferably between about 0.654.5 grams per liter. Below a hydrogen ion concentration of about 0.45 grams per liter, the etch rate is slow and peroxide decomposition high, particul'arly afler partial exhaustion of the peroxide bath.
  • the desired upper limit of the hydrogen ion concentration may depend on several factors including the particular acid employed. A hydrogen ion concentration above about 5.5 grams per liter is generally less economical and tends to slow down rather than increase the etch rate.
  • Inorganic acids and even the stronger organic acids, such as acetic acid, may be used to supply the hydrogen ion concentration in the etchant solution.
  • the acids which are the more suitable include sulfuric acid, nitric acid, and fluoboric acid, preferably sulfuric acid.
  • the amount of sulfuric acid in the hydrogen peroxide etchant is between about 2-23 percent by weight, preferably between about 3-20 percent by weight. Sulfuric acid concentrations above about 23 percent are less desirable in copper etching as they tend to result in les uniform dissolution, apparently caused by the formation of a protective coating on substantial portions of the exposed copper surface which is thereby made resistant to etching.
  • the hydrogen peroxide etchant may contain initially a high hydrogen ion concentration with relatively little sacrifree of etch rate after partial exhaustion and increase of the dissolved copper concentration.
  • the etchant solution may be advantageously made up to contain initially a low or intermediate hydrogen ion concentration, of the order of about OAS-3.4 grams per liter (about 2-15 percent by weight sulfuric acid), preferably between about 1.1-2.6 grams per liter (about 5-12 percent by weight sulfuric acid).
  • the etchant is consumed causing reduction of the hydrogen ion concentration
  • additional acid is added to regulate the hydrogen ion concentration within the optimum range of about 0.9-1.4 grams per liter (about 4-6 percent by weight sulfuric acid).
  • Addition of the acid may take place either continuously or intermittently and either immediately after the start of the etching or after significant exhaustion of the etchant solution.
  • the initial hydrogen ion concentration is low, say of the order of about O.45-1.l grams per liter (and 2-5 percent by weight sulfuric acid)
  • the addition of the acid preferably takes place substantially immediately after etching commences and is desirably more or less continuous until the hydrogen ion concentration is increased to well within the range of about 0.9-1.4 grams per liter.
  • the addition of acid to maintain the optimum concentration preferably takes place from time to time and after the etchant solution has been exhausted to the extent that the hydrogen ion concentration is below about 1.1 grams per liter, usually just after the concentration is reduced below about 0.9 grams per liter.
  • the ratio of hydrogen peroxide to acid is less important than the concentration of the acid.
  • a mol ratio of l to 2 is indicated, i.e. a l-1,0,/ H ratio of l to 2.
  • Peroxide to hydrogen ion mol ratios of less than 1 to 2 are therefore generally unnecessary and may tend to slow the etch rate, particularly at the higher reagent concentrations.
  • the amount of hydrogen peroxide actually consumed seldom will exceed about 75 percent so that the inclusion of just slightly more than about 1.5 mols of hydrogen ion per mol of peroxide will be adequate to supply sufficient acid for complete utilization of the particular etchant solution.
  • the etchants made up to include sufficient acid for complete utilization without addition of more acid preferably have a hydrogen peroxide to hydrogen ion mol ratio of not less than about 1.0 to 1.6, and desirably in the range of about :16 to 1.0 to 1.0.
  • the mol ratio of peroxide to acid hydrogen may, of course, be initially somewhat greater, preferably between about 10:02 to 1.0:1.0.
  • the mol ratio of peroxide to acid will be reduced and eventually become similar to the mol ratios preferably employed in the solutions made up to contain the complete acid requirement.
  • peroxide utilization seldom exceeds 75 percent, it is desirable from a practical viewpoint not to add an amount of acid sufficient to reduce the mol ratio of peroxide to acid hydrogen below about 1.0 to 1.6.
  • the temperature of the acidified-hydrogen peroxide solution is another important factor in etching copper. As a practical matter, copper metal is not etched at room temperatures or below. The nature of the attack of the acid hydrogen peroxide solution on copper at such temperatures is more of a polishing, oxidizing or brightening effect.
  • the hydrogen peroxide solution should have a temperature of at least about 40 C. when in contact with the metal.
  • the solution temperature has a strong effect on etch rates and increasing the temperature to a preferred range between about 5062 C. will substantially increase the rate of etching to a level significantly greater than heretofore realized with ammonium peisulfate etchants at recommended optimum temperatures.
  • etching may be commenced at the lower temperatures, for example, between about 40 C. to 55 C., and temperature of the solution then gradually increased up to a higher temperature of approximately 55-62 C. as the solution is further exhausted.
  • Some increase in the temperature of the etchant solution is caused by the moderately exothermic etching reaction itself.
  • Increasing the temperature of the etchant may be used to advantage to regulate etch rates at a more or less constant value when a number of pieces are to be etched in the same solution, for example, when employing automatic systems used in the manufacture of printed circuits.
  • the etchant compositions of the invention may be prepared by simple mixing of the required components.
  • aqueous hydrogen peroxide concentrate containing between about 20-70 percent, preferably between 30-60 percent by weight hydrogen peroxide and between about ZOO-20,000 parts per million, preferably between 5005,000 parts per million of the desired additive.
  • Such concentrates may also con tain silver ions in an amount between about ZOO-5,000 parts per million, preferably between about 5002,500 parts per million silver ions.
  • the silver ions are preferably furnished by addition of silver nitrate in an amount between about 3007,000 parts per million, more usually between 7503,50O parts per million.
  • the etchant solutions are readily prepared from the concentrates by addition of acid and water and, preferably, other desired additives such as sulfathiazole.
  • the hydrogen peroxide concentrate may be easily and safely shipped and has the further advantage of being storable for extended periods of time at room temperatures and above without depreciation.
  • the acid-hydrogen peroxide solutions of the present invention are eminently suited for etching of copper or other metal and they may be applied generally in other conventional chemical dissolving operations such as chemical milling, graining and bright dipping or polishing.
  • the temperature of the acid-peroxide solution may be varied, if desired, outside of the range prescribed for the etching of copper.
  • bn'ght dipping operations may be carried efiectively at room temperature or slightly above.
  • the additives provided by the invention are beneficially effective not only in the presence of copper but also other metal ions.
  • the acid solutions containing the additives may be employed in the dissolution of other metals such as iron, nickel, cadmium, zinc, germanium, lead, steel, aluminum and alloys containing a major portion of such metals.
  • Aluminum metal is more effectively dissolved when the acid employed is nitric acid or fluoboric acid, particularly fluoboric acid.
  • the solutions are however, less effective on certain other metals such as gold, tin, chromium, stainless steel and titanium.
  • the copper-clad laminates employed in the following examples were cut into specimens having dimensions of 2 /4. inch X 4% inch. Each specimen had 2.7 mil thick copper (2 ounces per square foot) laminated to a plastic base. Etch time was determined with a stopwatch and etch rate calculated after weighing each specimen before and after treatment.
  • EXAMPLE 1 A series of immersion etchants were prepared containing approximately 2,000 parts per million of a test compound in acidified hydrogen peroxide solutions having an analysis of 8 percent H 0 17 percent H SO and 267 parts per million Ag- N0
  • a stock etch solution was prepared by first mixing approximately 335 cc of 50 percent H O, with about 250 cc of 11,80 (93 percent electrolyte grade) and about 1,635 cc of tap water. To 500 gm. of this stock solution (445 ml.) were added approximately 1.0 gram of test compound resulting in an additive content of about 2,000 parts per million.
  • the 2-ounce copper laminated boards were etched l at a time.
  • EXAMPLE ii A second series of runs were made employing a etchant solution similar in composition to the one used in Example I, except that deionized water was employed.
  • the etchant contained 8 percent H,O,, 17 percent H,SO and 267 parts per million AgNO,.
  • Approximately :6 grams of additive compound was added to about 500 grams (445 ml) of the stock etchant solution, which when dissolved provided a concentration of about 1,000 parts per million. Some of the additives tested did not completely dissolve. in these instances the solution was stirred hot for at leat about 15 minutes and filtered.
  • the copper content of each of the etchant baths was determined at a terminating etch time of minutes for 2 ounces of copper. Additionally, the percent of the original hydrogen peroxide decomposed in the etchant while etching 9 A to 10 ounces of copper was determined. Etching was carried out at 60 C. These data are presented in Table ll, below.
  • the reduced decomposition of the ",O,, as exhibited by the etch solutions containing additive of the present invention can increase the useful etchant life up to about 30 percent or an additional 2 to 3 ounces of copper per gallon of etchant during a given period of time.
  • the method for dissolution of a metal selected from the group consisting of copper, iron, nickel, cadmium, zinc, steel, aluminum and alloys thereof which comprises contacting the metal at a temperature within the range from about 40 C. up to about 65 C. with an acidified aqueous hydrogen peroxide solution having incorporated therein at least about 2 weight percent hydrogen peroxide, about 0.45 to 5.5 grams per liter hydrogen ion and a catalytic amount of at least about 20 parts per million of an additive having the structure:
  • X is a member selected from the group consisting of oxygen and sulfur; and each of R, R R and R is a radical selected from the group consisting of hydrogen, a non-aromatic hydrocarbon radical; acyl; and monoand dinuclear aromatic hydrocarbon radicals wherein the aromatic ring may be bonded to the nitrogen atom through an alkylene or carbonyl group; said hydrocarbon radicals containing from 1 up to about 18 carbon atoms; provided that at least one of R, R, R and R is a radical other than hydrogen and provided further that when X is oxygen and up to two of R, R, Rand R is an unsubstituted phenyl, then at least one of said remaining R groups is a radical other than hydrogen.
  • the additive is selected from the group consisting of p-chlorophenyl urea, tolyurea, phenetylurea, N,N'-diethylcarbanilide, N,N-dimethylcarbanilide, benzoylurea, dibenzylurea.
  • each of R, R, R and R is a radical selected from the group consisting of hydrogen, a non-aromatic hydrocarbon containing from 1 to 12 carbon atoms and acyl derivatives of said hydrocarbons.
  • a composition for metal dissolution consisting essentially of an acidified aqueous hydrogen peroxide solution having incorporated therein at least about 2 weight percent hydrogen peroxide and a catalytic amount of at least about 20 parts per million of an additive having the structure:
  • X is a member selected from the group consisting of oxygen and sulfur; and each of R, R- and R is a radical selected from the group consisting of hydrogen, a non-aromatic hydrocarbon radical; acyl; and monoand dinuclear aromatic hydrocarbon radicals wherein the aromatic ring may be bonded to the nitrogen atom through an alkylene or carbonyl group; said hydrocarbon radicals containing from 1 up to about 18 carbon atoms; provided that at least one of R, R, R- and R is a radical selected from the group consisting of hydrogen, a non-aromatic hydrocarbon radical; acyl; and monoand dinuclear aromatic hydrocarbon radicals wherein the aromatic ring may be bonded to the nitrogen atom through an alkylene or carbonyl group; said hydrocarbon radicals containing from 1 up to about 18 carbon atoms; provided that at least one of R, R, R- and R is a radical selected from the group consisting of hydrogen, a non-aromatic hydrocarbon radical; acyl; and monoand din
  • R and R is a radical other than hydrogen and provided further that when X is oxygen and up to two of R, R, R and R is an unsubstituted phenyl, then at least one of said remaining R groups is a radical other than hydrogen.
  • composition of claim 11 in which the amount of additive incorporated therein is between about 50 to 2,000 parts per million.
  • composition of claim 11 in which there is also incorporated as catalyst an additive selected from the group consisting of sulfathiazole, phenacetin, silver ions and watersoluble salts and mixtures thereof.
  • composition according to claim 11 in which the solution has incorporated therein about 2 to 12 percent by weight hydrogen peroxide and about 0.45 to 5.5 grams per liter hydrogen ion.
  • composition according to claim 11 in which the solution has incorporated therein between about 2 to 23 percent by weight sulfuric acid.
  • composition according to claim 11 in which the total chloride and bromide ion content does not exceed 2 parts per million.
  • composition of claim 11 wherein the additive is present in an amount between and 5,000 parts per million.
  • X is a member selected from the group consisting of oxygen and sulfur; and each of R, R, R and R is a radical selected from the group consisting of hydrogen, a non-aromatic hydrocarbon radical; acyl; and monoand dinuclear aromatic hydrocarbon radicals wherein the aromatic ring may be bonded to the nitrogen atom through an alkylene or carbonyl group; said hydrocarbon radicals containing from 1 up to 18 carbon atoms; provided that at least one of R, R, R and R is a radical other than hydrogen and provided further that when X is oxygen and up to two of R, R, R and R is an unsubstituted phenyl, at least one of said remaining R groups is a radical other than hydrogen; said composition consisting essentially of a concentrated aqueous solution containing 20-70 percent hydrogen peroxide and at least one of said additives in a total amount between about 200-20,000 parts per million.
  • composition in accordance with claim 18 in which said concentrated aqueous solution has incorporated therein 30-60 percent hydrogen peroxide, and between about SOC-5,000 parts per million of the additive.
  • composition of claim 18 which additionally'has incorporated therein a compound selected from the group consisting of sulfathiazole, phenacetin, silver ions, and water-soluble salts and mixtures thereof.
  • composition of claim 18 which additionally has incorporated therein about 200 to 5,000 parts per million silver ions.

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  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
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  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • ing And Chemical Polishing (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
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US4233112A (en) * 1979-06-25 1980-11-11 Dart Industries Inc. Dissolution of metals utilizing an aqueous H2 SO4 -H2 O2 -polysulfide etchant
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US4401509A (en) * 1982-09-07 1983-08-30 Fmc Corporation Composition and process for printed circuit etching using a sulfuric acid solution containing hydrogen peroxide
US4636282A (en) * 1985-06-20 1987-01-13 Great Lakes Chemical Corporation Method for etching copper and composition useful therein
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US5340505A (en) * 1990-10-26 1994-08-23 Recytec Sa Method for dissolving radioactively contaminated surfaces from metal articles
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WO1998013536A1 (en) * 1996-09-24 1998-04-02 Cabot Corporation Multi-oxidizer slurry for chemical mechanical polishing
US5783489A (en) * 1996-09-24 1998-07-21 Cabot Corporation Multi-oxidizer slurry for chemical mechanical polishing
US5800859A (en) * 1994-12-12 1998-09-01 Price; Andrew David Copper coating of printed circuit boards
US6015506A (en) * 1996-11-26 2000-01-18 Cabot Corporation Composition and method for polishing rigid disks
US6033596A (en) * 1996-09-24 2000-03-07 Cabot Corporation Multi-oxidizer slurry for chemical mechanical polishing
US6068787A (en) * 1996-11-26 2000-05-30 Cabot Corporation Composition and slurry useful for metal CMP
US6083419A (en) * 1997-07-28 2000-07-04 Cabot Corporation Polishing composition including an inhibitor of tungsten etching
EP1031644A1 (de) * 1999-02-25 2000-08-30 Shipley Company LLC Thiazol- and Thiocarbamid- basierte Chemikalien zur Verwendung in oxidierenden Ätzlösungen
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US20040134873A1 (en) * 1996-07-25 2004-07-15 Li Yao Abrasive-free chemical mechanical polishing composition and polishing process containing same
US20040140288A1 (en) * 1996-07-25 2004-07-22 Bakul Patel Wet etch of titanium-tungsten film
JP2005187945A (ja) * 2000-12-27 2005-07-14 Ebara Udylite Kk 銅および銅合金用のマイクロエッチング剤
US20060173096A1 (en) * 2005-01-24 2006-08-03 Seiko Epson Corporation Aqueous ink composition, and ink jet recording method and recorded matter using the same
US20090095493A1 (en) * 2007-01-25 2009-04-16 Tini Alloy Company Frangible shape memory alloy fire sprinkler valve actuator
US20100006304A1 (en) * 2007-01-25 2010-01-14 Alfred David Johnson Sprinkler valve with active actuation
US20110039194A1 (en) * 2009-08-17 2011-02-17 Palo Alto Research Center Incorporated Solid inks for masks for printed circuit boards and other electronic devices
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US8858755B2 (en) 2011-08-26 2014-10-14 Tel Nexx, Inc. Edge bevel removal apparatus and method
US10124197B2 (en) 2012-08-31 2018-11-13 TiNi Allot Company Fire sprinkler valve actuator
US10610620B2 (en) 2007-07-30 2020-04-07 Monarch Biosciences, Inc. Method and devices for preventing restenosis in cardiovascular stents
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US6444140B2 (en) 1999-03-17 2002-09-03 Morton International Inc. Micro-etch solution for producing metal surface topography
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US8506767B2 (en) 2000-01-24 2013-08-13 Stryker Corporation Thin-film shape memory alloy device and method
US20030178391A1 (en) * 2000-06-16 2003-09-25 Shipley Company, L.L.C. Composition for producing metal surface topography
US20040099637A1 (en) * 2000-06-16 2004-05-27 Shipley Company, L.L.C. Composition for producing metal surface topography
JP2004003020A (ja) * 2000-12-27 2004-01-08 Ebara Udylite Kk 銅および銅合金用のマイクロエッチング剤並びにこれを用いる銅または銅合金の微細粗化方法
JP2005187945A (ja) * 2000-12-27 2005-07-14 Ebara Udylite Kk 銅および銅合金用のマイクロエッチング剤
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US6383065B1 (en) 2001-01-22 2002-05-07 Cabot Microelectronics Corporation Catalytic reactive pad for metal CMP
US20030150840A1 (en) * 2002-02-11 2003-08-14 Gould Electronics Inc. Etching solution for forming an embedded resistor
US6841084B2 (en) 2002-02-11 2005-01-11 Nikko Materials Usa, Inc. Etching solution for forming an embedded resistor
US20060173096A1 (en) * 2005-01-24 2006-08-03 Seiko Epson Corporation Aqueous ink composition, and ink jet recording method and recorded matter using the same
US20100006304A1 (en) * 2007-01-25 2010-01-14 Alfred David Johnson Sprinkler valve with active actuation
US20100025050A2 (en) * 2007-01-25 2010-02-04 Alfred Johnson Frangible Shape Memory Alloy Fire Sprinkler Valve Actuator
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US10610620B2 (en) 2007-07-30 2020-04-07 Monarch Biosciences, Inc. Method and devices for preventing restenosis in cardiovascular stents
US20110039193A1 (en) * 2009-08-17 2011-02-17 Palo Alto Research Center Incorporated Solid inks for printed masks
US8303832B2 (en) 2009-08-17 2012-11-06 Palo Alto Research Center Incorporated Solid inks for masks for printed circuit boards and other electronic devices
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US8858755B2 (en) 2011-08-26 2014-10-14 Tel Nexx, Inc. Edge bevel removal apparatus and method
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FR2019333A1 (de) 1970-07-03
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