Classifications

• • 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
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
  • C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
  • C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
  • C23C22/48—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 not containing phosphates, hexavalent chromium compounds, fluorides or complex fluorides, molybdates, tungstates, vanadates or oxalates
  • C23C22/52—Treatment of copper or alloys based thereon
• • 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
  • C23F3/00—Brightening metals by chemical means
  • C23F3/04—Heavy metals
• • 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
  • C23F3/00—Brightening metals by chemical means
  • C23F3/04—Heavy metals
  • C23F3/06—Heavy metals with acidic solutions
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/22—Secondary treatment of printed circuits
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/03—Metal processing
  • H05K2203/0392—Pretreatment of metal, e.g. before finish plating, etching
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/07—Treatments involving liquids, e.g. plating, rinsing
  • H05K2203/0779—Treatments involving liquids, e.g. plating, rinsing characterised by the specific liquids involved
  • H05K2203/0786—Using an aqueous solution, e.g. for cleaning or during drilling of holes
  • H05K2203/0789—Aqueous acid solution, e.g. for cleaning or etching

Definitions

• the invention relates to a method of chemically polishing, more particularly polishing copper, by a simple immersion of the articles to be polished in three successive baths at the ambient temperature.
• the polishing may also constitute a preparation for a later operation, for example, a weld or a deposit of another metal on the copper.
• the brilliant appearance given by the polishing permits of judging the quality of the polish necessary for a ready solderability or to obtain a deposit of the desired quality. It is known actually that, the appearance of articles covered with a deposit, the ease of the soldering, the resistance to corrosion depend upon the state of the surface of the metal of the base.
• the polishing of the copper and copper alloys may be achieved by different methods.
• a mixture of acids may be used of which the composition varies within the following limits in accordance with the method to be treated:
• the duration of the bath is from 2 to 6 minutes and the temperature from 55 to 80 C.
• the invention avoids these drawbacks and has for its object to provide a method of chemically polishing copper and copper alloys consisting of immersing the article to be polished in three successive baths;
• a second bath of H 0 which oxidizes the said film and renders the surface stable in air;
• a third bath of HNO which dissolves the said oxidized film and produces the polish.
• the treatments are carried out at the ambient temperature.
• the glycerin due to the viscosity which the hydroxyl group gives it, has two effects: it retards the reaction speed of the attack and forms on the elements to be polished a protecting layer which permits of performing the passage from the first to the second bath less rapidly without having to fear the action of the air.
• This oxidation treatment of the second bath which modifies the absorbed layer is an important characteristic of the method according to the invention. In fact it has been found that if one passes immediately from the first bath to the third, the surface of the copper will be dull and unsuitable for being coated ultimately with metal.
• the brown layer of oxide formed in the second bath is stable and is not modified by a stay in the air.
• the copper need no longer be pickled, unless the superficial oxidation is excessive; when the amount of grease is important, the copper must be degreased but finger prints, for example, do not matter;
• the activities are constantly carried out at the ambient temperature
• the bath is sufiiciently stable
• the articles may be preserved after oxidation without the underlying surface being altered.
• the articles obtained are particularly brilliant; their surface permits of a perfect solderability and an excellent quality of the metal deposits, notably those realised by displacement or reduction, which are very sensitive to their surface state.
• the shine of these articles is particularly stable.
• Another advantage is the possibility of varying the reaction speed in accordance with the article to be polished as may appear from the example of the method to be described below.
• a particularly brilliant surface of copper is obtained by dipping the metal successively in the following solutions:
• Second bath-hydrogen peroxide H 0 33.3% by weight.
• the elements to be polished are treated in the first bath for from 30 to 45 seconds and are then rapidly dipped in the second bath until a brown gold-plated colour is ob tained as uniformly as possible. Then these elements are dipped in the third bath until the polish appears.
• composition of the first bath as follows:
• the volume is brought to 600 ml. with a solution of E.D.T.A. (ethylene diamine tetra-acetic acid or a complex ion thereof) of 10 gr./1.
• E.D.T.A. ethylene diamine tetra-acetic acid or a complex ion thereof
• E.D.T.A. forms a complex with the copper during the reaction thus avoiding the decomposition of the hydrogen peroxide by the copper ions which augments the stability of the bath.
• thefirst bath may be modified according to the nature of the copper to be treated (thin layers, heating, etc.) in a manner such as to adapt the mixture to the thickness tolerance of the copper to be obtained while the final polishing succeeds all the same.
• concentration of the three products composing solution 1 may be varied. For example, if the hydrochloric concentration is diminished, the solution may give a favourable surface not only in the case of copper but also in the case of brass.
• a method of chemically polishing an article essentially consisting of copper comprising the steps, immersing said article in a first bath consisting essentially of hydrochloric acid, glycerine and hydrogen peroxide, immediately after withdrawal from said first bath immersing said article in a second bath consisting of a 33.3% by weight solution of hydrogen peroxide and then immersing said article in 0.250.5 N nitric acid.
• a method of chemically polishing a copper article comprising the steps immerisng said article in a first bath consisting of 200 ml. of 6 N hydrochloric acid, 100 ml. of 33.3% by weight hydrogen peroxide and ml. of glycerine, immediately thereafter immersing said article in a second bath consisting of a 33.3% by weight solution hydrogen peroxide and then immersing said article in a third bath consisting of 025-05 N nitric acid.
• a method of chemically polishing a copper article comprising the steps immersing said article in a first bath consisting of 200 ml. of 6 N hydrochloric acid, ml. of 33.3% by Weight hydrogen peroxide and a suflicient amount of a 10 gram per liter solution of ethylene diamine tetraacetic acid to bring the volume of said bath to 600 ml. immediately thereafter immersing said article in a second bath consisting of a 33.3% by Weight solution hydrogen peroxide and then immersing said article in a third bath consisting of 025-05 N nitric acid.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Metallurgy (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Manufacturing & Machinery (AREA)
• Microelectronics & Electronic Packaging (AREA)
• ing And Chemical Polishing (AREA)
• Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
• Chemical Treatment Of Metals (AREA)

Applications Claiming Priority (1)

Publications (1)

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ID=8811563

Family Applications (1)

Country Status (7)

Cited By (7)

Families Citing this family (1)

Citations (2)

Family Cites Families (2)

• 0
  • BE BE652530D patent/BE652530A/xx unknown
• 1963
  • 1963-09-02 FR FR946304A patent/FR1375201A/fr not_active Expired
• 1964
  • 1964-08-28 GB GB35334/64A patent/GB1062103A/en not_active Expired
  • 1964-08-31 DE DEN25440A patent/DE1289381B/de active Pending
  • 1964-08-31 US US393400A patent/US3345225A/en not_active Expired - Lifetime
  • 1964-08-31 CH CH1134864A patent/CH461918A/de unknown
  • 1964-12-30 OA OA51141A patent/OA01050A/xx unknown

Patent Citations (2)

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