WO2004103040A2 - Verfahren zur beschichtung von rohlingen zur herstellung von gedruckten leiterplatten (pcb) - Google Patents
Verfahren zur beschichtung von rohlingen zur herstellung von gedruckten leiterplatten (pcb) Download PDFInfo
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- WO2004103040A2 WO2004103040A2 PCT/AT2004/000168 AT2004000168W WO2004103040A2 WO 2004103040 A2 WO2004103040 A2 WO 2004103040A2 AT 2004000168 W AT2004000168 W AT 2004000168W WO 2004103040 A2 WO2004103040 A2 WO 2004103040A2
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- WIPO (PCT)
- Prior art keywords
- pcb
- blank
- acid
- protective film
- monolayer
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Classifications
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- 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
- H05K3/02—Apparatus or processes for manufacturing printed circuits in which the conductive material is applied to the surface of the insulating support and is thereafter removed from such areas of the surface which are not intended for current conducting or shielding
- H05K3/06—Apparatus or processes for manufacturing printed circuits in which the conductive material is applied to the surface of the insulating support and is thereafter removed from such areas of the surface which are not intended for current conducting or shielding the conductive material being removed chemically or electrolytically, e.g. by photo-etch process
- H05K3/061—Etching masks
-
- 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
- C23C22/02—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 non-aqueous solutions
-
- 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
- C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
-
- 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
- C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
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- 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
- H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
- H05K2201/02—Fillers; Particles; Fibers; Reinforcement materials
- H05K2201/0203—Fillers and particles
- H05K2201/0206—Materials
- H05K2201/0239—Coupling agent for particles
-
- 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
- H05K2203/05—Patterning and lithography; Masks; Details of resist
- H05K2203/0562—Details of resist
- H05K2203/0577—Double layer of resist having the same pattern
-
- 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
- H05K2203/10—Using electric, magnetic and electromagnetic fields; Using laser light
- H05K2203/107—Using laser light
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
Definitions
- PCB printed circuit boards
- the present invention relates to a method for coating blanks for the production of printed circuit boards (PCB) and blanks coated in this way for the production of PCBs.
- PCB printed circuit boards
- a blank for PCBs epoxy resin-impregnated glass fabric with a copper coating on one or both sides is particularly suitable.
- any metal-coated carrier is subsumed below under the term PCB blank. Suitable metals are in particular platinum, titanium, silver, gold, nickel, zinc, iron or alloys thereof, alloys such as steel and brass, but also metal oxides such as copper oxide, aluminum oxide and iron oxide.
- the hole filling process has gained the most widespread use in the production of plated-through copper PCBs.
- process steps such as drilling, electroplating, photo and etching processes, etc.
- a plated-through printed circuit board made of copper is obtained.
- the electrolytic solder plating method is inexpensive in that it can produce a plated-through printed circuit board with high reliability, but has the disadvantage that it requires a long manufacturing time, a high manufacturing cost and a large amount of chemical treatment, which cause pollution and high expenditure on Require countermeasures against pollution. Therefore, it has become necessary to provide a process which is faster to manufacture and low in cost.
- the dissolved alkylimidazole compound has a high reactivity with copper and an imidazole coating is thereby formed on the surface of the copper. It is known that due to the action of hydrogen bonding among the long-chain alkydimidazole molecules and because of the van der Waals forces, the alkylimidazole molecules present in the treating aqueous solution continue to deposit on the surface of the coating and the coating thereby separates further thickened.
- the connection is cheaper, safer and easier to remove than the photosensitive polymer resist films known in the prior art, resists alkaline etching and therefore protects the copper-plated parts of the blank from an etching solution.
- the acid resist film can be made from an organic compound (oligomer or low molecular weight polymer and combinations of both), both of which contain a hydrophilic group and a hydrophobic part.
- the hydrophilic group is a polar group with a strong affinity or reactivity to copper.
- the hydrophobic part has a long alkyl group with 5 to 21 carbon atoms and has water-repellent properties.
- SAMs self-aggregating monolayers
- SAMs derived from these organic molecules are useful in blocking electron transfer or as corrosion inhibitors (they limit the diffusion of oxygen, water and aqueous ions).
- Cross-linked SAMs result in more robust films with improved degrees of protection.
- SAMs provide more flexible systems with easier processing to form partially crystalline barrier films on copper.
- the formation of barrier films is the result of a simple chemical adsorption process and thin, uniform, conformal films are produced.
- the use of the strong chemical adsorption of alkanethiols on copper has been widely used in practice.
- the preference for the long chain adsorbates has been explained in terms of larger cohesive interactions between long alkyl chains in the monolayer.
- the thiols are chemically bonded directly to the metal surface through the formation of Cu-S bonds.
- the formation is highly exothermic and provides a strong driving force for adsorption.
- the initial adsorption is fast, with the result that about 90% of the final monolayer coverage is obtained within seconds.
- the molecules undergo a slower ordering process, which can last from several minutes to several days, depending on the chemical structure of the derivatives used.
- Several factors influence the formation and packing density of the monolayers, such as the type and unevenness of the support, the solvent used, the type of adsorbate, temperature and the concentration of the adsorbate.
- Cleanliness and crystallinity of the carrier also play a crucial role in determining the compactness, which is often quantitatively assessed by the pinhole distribution (i.e. the distribution of smallest holes).
- pinhole distribution i.e. the distribution of smallest holes.
- For most wearers, rigorous cleaning treatments and wear and tear are required prior to monolayer formation. ger pretreatment necessary.
- a very dilute solution results in ordered monolayer, while a high concentration and long time favor multilayer formation (Kim, 1993).
- Chain length is another important parameter since a dense monolayer can be obtained by controlling chain length to achieve crystalline nature (Porter, 1987). Phenyl and biphenyl systems also show good packing due to the ⁇ - ⁇ interactions, but they are less stable than those of the long-chain adsorbates (Aslam, 2001).
- SAMs formed from long-chain adsorbates are superior to the shorter-chain analogues in maintaining their structure and properties due to the Van der Waals interactions.
- a film's ability to maintain its barrier properties scales exponentially with the chain length of the n-alkanethiol, with five additional methylenes in the chain resulting in films that are twice as effective in maintaining their barrier properties.
- Electrochemical measurements of heterogeneous electron transfer rates and differential capacitance indicate that the long-chain monolayers are free of pinholes, provide substantial barriers to electron transfer, and are highly resistant to ion penetration (Tao, 1994).
- Long-chain alkanethiols (HS (CH 2 ) n X) with a polar and non-polar terminal group can adsorb onto the surface of freshly prepared Cu surfaces from solution and form an aligned monolayer (Laibinis, 1992).
- ⁇ -terminated alkanethiolate monolayers consist of trans-extended chains with orientations on copper that are close to the perpendicular to the surface.
- X -OH, -CONH 2 , -COOH etc.
- Alkylsiloxane monolayers are made from alkylsilanol precursors on a variety of OH-terminated Surfaces formed.
- the surface OH groups act as active participants in the nucleation and growth of these films (Rye, 1997).
- the surface concentration of hydroxyl groups which serve as nucleation centers and anchor points in the film formation process, can have an extended influence on the growth process and the film structure of the submonolayer.
- the specific conditions of the film production such as the water content of the adsorbate solution, the solvent, the precursor concentration or the type and pretreatment of the carrier must be considered.
- the structure of the submonolayer films depends heavily on some of these parameters.
- the water concentration on the carrier surface influences the rate of surface polymerization and surface diffusion of the film molecules.
- the size of the primary islands deposited on the support also depends on the degree of polymerization of silanol precursors in the adsorbate solution, which in turn depends on a variety of factors including the water content, the reaction time
- the properties of the corrosion protection layers have been improved by chemical modification of the self-aggregating layer with various coupling agents.
- a self-aggregating monolayer of 11-mercapto-l-indecanol (MUO) (Itoh, 1995), chemically adsorbed on an oxide-free copper surface, was modified with alkyltrichlorosilanes C 8 H 37 SiCl 3 .
- the modified MUO layer is hydrolyzed with water, followed by spontaneous polymerization to form a regularly arranged polymer monolayer on the Cu surface. This film was significantly protective against aqueous and atmospheric corrosion of copper (Ishibashi, 1996).
- Alkane phosphoric acids are coatings for natural oxide surfaces of metals or alloys, such as tin, iron, steel, aluminum, copper (Alsten, 1999) and various flat oxide carriers (Ti0 2 , Nb 2 0 5 and A1 2 0 3 ).
- the films were produced by self-aggregation from a heptan-propan-2-ol solution. Contact angle measurements and X-ray fine structure spectroscopy close to the absorption edge indicate that these layers were formed similar to the thiol-gold systems and provide access to potential applications in the area of corrosion protection. Different methods for connecting self-aggregating monolayers to one another have been developed in the third dimension.
- the polymeric multilayers are highly cross-linked and much thicker than a single SAM.
- Polymeric coatings with high levels of crystallinity and tight packing are more effective in reducing the diffusion of water and have good mechanical properties (heat, shrink, impact, crack, resistance and good extensibility, adhesion and processability), which are suitable for industrial production.
- polymeric coatings such as polyimides (Bellu ⁇ ci, 1991) and polystyrene (Kurbanova, 1997) are often used to protect metals against corrosion.
- the polymeric layer acts as a thick, hydrophobic barrier that prevents the transport of water and other corrosive agents.
- the polymer can easily be produced as a thin film by spin coating processes (Stange, 1992).
- a combination of organothiol SAM and polystyrene polymer has been investigated (Jennings, 1999).
- Atomic force microscopy (AFM) images of the films revealed a complete film with no evidence of defects.
- a 40 ⁇ m cast film contains C0 2 -H-modified pole (vinyl alcohol) and shows good acid resistance. If it is converted to the salt form by adding NaOH, it is easily dissolved in water (JP-10/060207 A).
- a carboxylic acid terminated SAM with a polymer multilayer which poly (ethyleneimine) and poly (octadecen-alt-maleic anhydride) (POMA, Mw 30,000) or poly (styrene-alt-maleic anhydride (PSMA) as effective Corrosion protection (Kl-based commercial gold etching) gave the best result (Huck, 1999).
- poly (ethyleneimine) and poly (octadecen-alt-maleic anhydride) (POMA, Mw 30,000) or poly (styrene-alt-maleic anhydride (PSMA) as effective Corrosion protection (Kl-based commercial gold etching) gave the best result (Huck, 1999).
- PSMA poly (styrene-alt-maleic anhydride)
- Kl-based commercial gold etching Kl-based commercial gold etching
- the acid-resistant protective film of a blank PCB consists of at least 2 layers which are chemically bonded to one another or to the metallic surface of the blank PCB. Due to the chemical bond Probably the first monolayer with the metallic surface of the PCB blank as well as every further monolayer with the underlying monolayer, it is possible to provide extremely thin protective films while avoiding pinholes due to the topography of the metallic surface of the blank or local wetting problems.
- the protective film of the PCB blank preferably has a thickness of less than 20 ⁇ m, more preferably less than 10 ⁇ m and most preferably less than 4 ⁇ m.
- the protective film of the PCB blank preferably has a thickness of less than 20 ⁇ m, more preferably less than 10 ⁇ m and most preferably less than 4 ⁇ m.
- the problem of channel formation during the manufacture of the PCBs in particular can be prevented.
- this problem is that in most laser-assisted PCB manufacturing, the width of the trace combustible into the surface of the coated blank PCB depends on the thickness of the protective film in that a ratio of 1: 1 (thickness of the protective film plus thickness of the Metal coating of the blank: width of the track) should not be undercut.
- the at least 2 layers of the protective film are each formed by a compound of the general formula
- W represents -SH, -Si (X) 3 , -Si (OR) X 2 , -Si (0R) 2 X, -Si (OR) 3, -COOH, -P0 3 H 2 ,;
- X represents fluorine, chlorine, bromine or iodine
- Y represents -OH, COOH, -P0 3 H 2 .
- the invention is based on the knowledge that, due to the functional group W, the above-mentioned classes of compounds have a high degree of adsorption power with respect to metallic surfaces and a covalent bond is formed during the adsorption.
- Conventional pure metals such as copper, in particular also the elements of the sub-group of the periodic table (e.g. platinum, titanium, silver, gold, nickel, zinc, iron or alloys thereof), alloys such as steel and brass, but also metal oxides such as copper oxide, aluminum oxide and Iron oxide, can be used as metal coatings on the PCB blanks. Due to the strong adsorption force of the W-functional group in relation to the metallic surface, it is possible to deposit a monomolecular coating (monolayer) on the metallic surface. As a result, only a small amount of adhesive substance is required, which is cost-effective. Furthermore, the chemical bond between the monolayers or between the first monolayer and the metallic surface of the blank PCB overcomes wetting problems.
- the adhesive substance is a thiol (-SH) -, silane (-Si (Cl) 3 , -Si (0R) 2 Cl, -Si (OR) Cl 2 , -Si (OR) 3 ) -, organophosphoric acid (-P0 3 H 2 ) - or organcarboxylic acid (-COOH) group as W, which has a covalent bond to the metal surface (such as Cu-S) can train.
- thiol (-SH) -, silane (-Si (Cl) 3 , -Si (0R) 2 Cl, -Si (OR) Cl 2 , -Si (OR) 3 ) -, organophosphoric acid (-P0 3 H 2 ) - or organcarboxylic acid (-COOH) group as W which has a covalent bond to the metal surface (such as Cu-S) can train.
- adsorption with respect to the metallic surface occurs, which is spontaneous to a large extent, which produces
- R alkyl radical, halogenated alkyl radical, alkyl radical or halogenated alkyl radical with hydroxyl group in the chain or aromatic group
- R alkyl radical, halogenated alkyl radical, alkyl radical or halogenated alkyl radical with hydroxyl group in the chain or aromatic group
- n is particularly preferably an integer from 10 to 22.
- the chain length of R and thus to a certain extent also the thickness of the monolayer can be varied from n.
- R can also be an aromatic unit and preferably has halogen and / or hydroxyl substituents in the aromatic system. Depending on the nature of the substituents, these in turn can influence the bond to the metallic surface or the further coating of the monofilm. As a result, the film can form an optimal, dense, hydrophobic space to prevent an etchant from reacting with the metal surface.
- Y preferably stands for -OH, -COOH or -P0 3 H 2 and can therefore react easily in the case of a homocoating with the functionality group W of the or a further compound W (R) Y to form a multilayer.
- a hydroxyl group reacts with a silane molecule to form a covalent bond (for example, an O-Si-O bond.
- the first layer is formed by a compound of the general formula
- Z represents Si (OR 2 ) 2 X, -Si (OR 2 ) X 2 , -SiX 3 , -P0 3 H 2 ,
- R, X and n has the meaning given above.
- n is particularly preferably in each case an integer from 10 to 22 independently of one another.
- the acid-resistant protective film of a blank PCB preferably has an organo-soluble or alkali-soluble polymer as the top or cover layer, which polymer has been selectively applied to the surface of the multilayer.
- the coating of the polymer on the protective film according to the invention protects the functionality L. In this way, sufficient adhesion between the polymer and the multilayer is generated.
- the task of the polymer film is to improve the mechanical properties of the multilayer, such as heat, shrinkage, impact, crack resistance as well as adhesion and processing ability. A number of polymers can be used for this.
- alkali-soluble polymer it is composed of acrylic acid, sulfonic acid, maleic acid and their ester copolymers rn.it S / x' ⁇ . ⁇ ., Oiiti-e-thylsil n, styrene, olefin, isobutylene, vinyl, ethene, imide , Methylstyrene, acrylamido, vinyl ether, ethylene-co-vinyl acetate, ethylene etc.
- the typical alkali-soluble polymer resins are based on a polymer which contains a -S0 3 H, -COOH group, or its alkali metal salt or its ester, for example Poly (di ethylsiloxane) graft polyacrylate, poly (acrylic acid), poly (sodium 4-styrene sulfonate), poly (4-styrene sulfonic acid co-maleic acid), poly (styrene / ⁇ -methyl styrene / acrylic acid), poly (dimethylsilane) monomethacrylate, poly (2-acrylamido-2-methyl-l-propanesulfonic acid), poly (2-acrylamido-2-2methyl-l-propanesulfonic acid-co-styrene), poly (styrene-alt-alic acid), poly (methyl vinyl ether-old maleic acid), poly (sodium methacrylic acid), poly (maleic acid-co-olefin
- the present invention further relates to a method for coating PCB blanks with an acid-resistant protective film, comprising the following steps: a) optionally pre-cleaning, drying, activating and / or surface treatment of the blank PCB b) forming a first monolayer on the metal surface of the blank PCB by applying a compound of the general formula
- W represents -SH, -Si (X) 3 , -Si (0R) X 2 , -Si (OR) 2 X, -Si (OR) 3 , -COOH, -P0 3 H 2 ,;
- X represents fluorine, chlorine, bromine or iodine
- Y represents -OH, COOH, -P0 3 H 2 .
- c) Forming at least one further monolayer on the first monolayer of the .PCB blank by applying either: c) l) a compound of the general formula
- Z represents Si (OR 2 ) 2 X, -Si (OR 2 ) X 2 , -SiX 3 , -P0 3 H 2 ,
- R, X and n have the meaning given above, d) optionally repeating step c) a number of times and e) optionally forming a cover layer on the uppermost monolayer of the PCB blank from an organo-soluble or alkali-soluble polymer.
- n preferably independently denotes an integer from 10 to 22.
- the compounds for providing the individual monolayers are applied in solution.
- connection for the provision of the individual monolayers are preferably applied by immersing the blank PCB in corresponding solutions of the individual connections.
- immersion is understood to mean any process by which the blank PCB is brought into contact with the corresponding solutions of the individual connections, for example by direct passage through the solution (s), by meniscus coating or by roller coating.
- the state of the metallic surface of the PCB blank can influence the molecular organization, monolayer coverage and the thickness of an adsorbed monolayer.
- the blanks are optionally pre-cleaned, for example, by a chemical process (Ingo-pure, NPS and HC1) and then dried in hot air. Afterwards, the blanks can be immersed in isopropanol for surface activation and rinsed with water. Thereafter, if desired, suitable surface treatment methods, such as chemical etching using an inorganic acid (HC1, HN0 3 , H 3 P0 4 , H 3 B0 3 , H 2 S0 4 , HC10 4 etc.), polishing and cathodic reduction can also be used Polishing the blank can be applied.
- suitable surface treatment methods such as chemical etching using an inorganic acid (HC1, HN0 3 , H 3 P0 4 , H 3 B0 3 , H 2 S0 4 , HC10 4 etc.), polishing and cathodic reduction can also be used Polishing the blank
- HCl etching results in an oxide-free surface
- Cl " in HC1 can be adsorbed onto the copper surface during the etching, which can reduce the adsorption capacity of the surface to form monolayers and lead to corrosion on the cleaned surface.
- the metallic surface of the blank consists of copper and is etched in an oxidizing acid such as nitric acid
- an oxide-copper surface can be formed, which seems to favor the special adsorption of organosilanes ..
- the upper layer of the copper atoms was removed from the copper surface by phosphoric acid or boric acid (non-oxidizing acids) removed and the cleaned surface can be used for a can be kept in air for a relatively long time without significant oxidation.
- nitric acid (4N), phosphoric acid (20% vol / vol), orthophosphoric acid (66% vol / vol) and boric acid (20% vol / vol) etching were preferred for a certain time (from 5 min up to several hours, typically 5 min) at room temperature, followed by purging in water and drying in nitrogen or an oven at 60-100 ° C to form a fresh, active and hydrophilic surface which demonstrates the chemical adsorption of alkanethiol, Alkane silane and alkane phosphoric acid strongly favored.
- the copper-clad PCB blank After washing twice with anhydrous ethanol, the copper-clad PCB blank is immersed in an ethanol solution of thiols at room temperature for a certain time (from 1 min to several days, typically 5-15 min) in order to chemically adsorb the thiol to complete on the copper surface. Excess thiol can be removed from the support surface by rinsing the surface with ethanol, after which the blank PCB is oven dried (from 30-150 ° C, typically 80 ° C).
- the organothiols used, for example, when performing the monolayer adsorption are based on the structure:
- W (R) Y with the meanings given above, e.g. 1-dodecanethiol, 1-octadecanethiol, 3-mercapto-l, 2-pr ⁇ pandiol; 4-mercaptophenol 6-mercapto-1-hexanol, 3-mercapto-l-propanol, 11-mercapto-l-undecol, 2-mercaptoethanol, 4-mercapto-l-butanol or 4-mercaptobutylphosphoric acid.
- either the above process for forming a second monolayer is repeated or the mono-coated PCB blank obtained in the above process at room temperature in, for example, a cyclohexane solution from organosilanes from 1 min up to submerged for several days (typically 5-15 min).
- organosilanes typically 1 min up to submerged for several days (typically 5-15 min).
- Other solvents that can be used in the application of organosilane are, for example, toluene, a mixture of hexadecane-carbon tetrachloride-chloroform 80: 12: 8, n-hexane, tetrahydrofuran, etc.
- the surface can be rinsed thoroughly with chloroform to remove excess organosilane, followed by placing the PCB blank treated in this way in an oven (temperature from 50 ° C. to 150 ° C. for 1 min to several hours) in order to remove the solvents and to harden the multilayer, as a result of which crosslinking can also be formed in the multilayer .
- the PCB blanks are then placed at normal temperature in a high humidity box (over 85%) for wet hardening (from several minutes to several days). Wet hardening is favorable for the further conversion from Si-Cl bond to Si-O bond and for uniform network formation in the multilayer. (d) Form a multi-coating
- the compounds for multilayer formation are based on the above-mentioned compound of the general formula
- Z (R) L having the above meanings, including: methyltrichlorosilane, ethyltrichlorosilane ethyldichlorosilane, propyltrichlorosilane, butyltrichlorosilane, isobutyltrichlorosilane, Pentyltrichlorsilan, hexyltrichlorosilane, octyltrichlorosilane, decyltrichlorosilane, decyl, dodecyltrichlorosilane, ethyldichlorosilane dodecyl, octadecyl-me- thyldichlorsilan, octadecyltrichlorosilane, benzyltrichlorosilane, Undecyltrichlorosilane, 2- (bicyclo-eptenyl) dimethylchlorosilane,
- the defect diameters of SAMs which are used as etch-resistant films, are sometimes too high to make PCB blanks coated in this way directly usable in the industrial production of high-resolution electronic devices.
- SAMs which are used as etch-resistant films
- the multi-layer PCB blank is treated with a polymer base solution.
- the aim of the treatment is: (l) to convert any remaining Si-Cl bonds into Si-OH, a silanol group, so that cross-linking can occur between the monolayers and (2) one on the blank PCB to provide a thin polymer film as a cover film, which cover film is effective in reducing the diffusion of water and has good mechanical properties (heat, shrink, impact, tear resistance and good elongation, adhesion and processing ability), which it for industrial Makes production suitable.
- the blank PCB is then dried in an oven at 50-150 ° C (typically 120 ° C) for 5-30 minutes (typically 15 minutes).
- the typical alkali-soluble polymer resins are based on a polymer which contains a -S0 3 H or -COOH group, or its alkali metal salt or its ester, for example poly (dimethylsiloxane) graft polyacrylate, poly (acrylic acid), poly (sodium 4-styrene sulfonate), poly (4-styrene sulfonic acid-co-maleic acid), poly (styrene / ⁇ -methylstyrene / acrylic acid), poly (dimethylsilane) -monomethacrylate, poly (2-acrylamido-2-methyl-l -propanesulfonic acid), poly (2-acrylamido-2-2methyl-l-propanesulfonic acid-co-styrene), poly (styrene-old-maleic acid), poly (methyl-vinylether-old-maleic acid), poly (sodium methacrylic acid), poly (maleic acid) -co-
- the principle of the hydrophobic-hydrophobic or hydrophilic-hydrophilic combination should be observed.
- the interfacial agents or specific interactions between the polymers are believed to reduce interfacial tension and thereby improve interfacial adhesion to efficiently transfer stress from one phase to the other phase. These specific interactions include hydrogen bonding, charge exchange complex formation, ion-dipole and ion-ion interaction.
- the acid-resistant protective layer is first coated on the copper-plated blank PCB and then patterned with a C0 2 or UV laser to destroy it to form a special configuration.
- the unwanted copper is then etched out at the appropriate, protective layer-free points by HCl-CuCl-CuCl 2 solution.
- the problem now is to completely remove the remaining acid-resistant protective layer.
- the detachment process includes both polymer detachment and SAMs detachment.
- Polymer detachment The polymer used for this purpose is alkali-soluble or organic-soluble and can therefore be easily separated with the appropriate solutions or solvents.
- Multi-layer separation The remaining problem is how to remove the individual monolayers.
- the SAMs are chemically bound to the carrier and the bonds should break either by chemical processes (hydrolysis, oxidation) or by photo processes (photo degradation).
- the SAM film is highly hydrophobic. It is only soluble in organic solvents.
- ODS submonolayers which are adsorbed on Cu carriers, are subjected to UV ozone oxidation (UV / ozone can be generated by a low-pressure mercury quartz lamp 185 or / and 254 nm), which, for example, leaves behind the two-dimensional cross-linked Si-0 network of the siloxane monolayer.
- UV ozone oxidation UV ozone oxidation
- UV / ozone can be generated by a low-pressure mercury quartz lamp 185 or / and 254 nm
- Photo-oxidation from RS to RS0 3 is too slow to be convenient, and the rate of this reaction can be accelerated by transition metal cations.
- Alkanesulfonates, which result from photo-oxidation, are only weakly bound to copper supports and can therefore be easily removed from its surface.
- the photo-oxidation process using a low-pressure mercury quartz lamp is only used in the laboratory for small sample treatment and is only of limited suitability for industrial PCB processes.
- the resist layer (that is, acid-resistant protective layer and polymer layer) is treated by a chemical hydrolysis method, whereby the resist layer can be removed in a short time.
- the stripping system used in this invention is as follows: (1) Organophosphoric acid and organosilane can be hydrolyzed under alkaline conditions. Therefore, the purpose of choosing an alkali-organic system is the solubility of the polymer and the long alkyl chain as well as the hydrolysis of PO, Si-O bonds.
- the organic alkali solution is based on a salt of an alkali metal (sodium or potassium hydroxide) dissolved in an alcohol (ethanol, 2-propanol, 1-butanol, isobutanol, 2-butanol, etc.).
- concentration of the solution is in the range of 1% to 30% w / w. (typically 20%).
- the temperature is raised to the range of 25 to 80 ° C (typically 60 ° C).
- polymeric substances and SAMs of the acid-resistant protective layer can be easily and cleanly removed from finished PCBs by the above processes without etching the underlying metal, in particular copper and copper alloys.
- Copper-clad PCB blanks are cleaned in 20% phosphoric acid solution at room temperature for 5 min, rinsed in water and oven dried at 100 ° C for 5 min to form a hydrophilic surface.
- the PCB blanks are then immersed in a 1.5% 6-mercapto-1-hexanol-ethanol solution at room temperature for 15 minutes, rinsed with pure ethanol and then dried in an oven at 100 ° C. for 5 minutes.
- a further monolayer is created by immersing the support in 3% octadecyltrichlorosilane-cyclohexane solution at room temperature for 15 minutes and then placing the support in an oven for curing at 120 ° C. for 10 minutes and thickening by repeating the above procedure.
- the PCB blanks are then wet cured in a highly humid atmosphere (over 85% LF) for several hours at room temperature.
- the coated PCB blanks are etched with a strong acid etching solution (HCl-CuCl 2 -CuCl) and then with a (NaOH / 2-propanol 20%) - Solution treated at 60 ° C for 5 min.
- the hydrolysis process can be accelerated by immersing it in an ultrasonic bath.
- the inorganic and organic impurities or residues are removed from the metal surface using an HF / H 2 0- (1%) and HC1 / H 2 0- (5%) acid solution.
- the PCB blanks are rinsed with water and dried in the oven or hot air. There- a very clean and structured copper-clad surface was obtained on the PCB blanks.
- Copper-clad PCB blanks are cleaned by removing the natural oxide by immersing them in a dilute HN0 3 solution (10% in deionized water) for 5 minutes. Then, after repeated cleaning with water and isopropyl alcohol, the PCB blanks are dried in a stream of nitrogen gas to form a hydrophilic surface.
- the first monolayer is then formed by immersing the freshly cleaned PCB blanks in a 3% solution of octadeyltrichlorosilane, dissolved in hexadecane, at room temperature for 15 minutes.
- the PCB blanks provided with a first monolayer are cured in the oven at 120 ° C. for 10 min and then the process is repeated.
- the double coating creates a homogeneous film on the surface of the PCB blanks.
- the PCB blanks are then wet-cured for one hour in a high humidity box (humidity above 85% LF).
- Copper-plated PCB blanks are immersed in 4N HC1 solution for 5 min.
- the PCB blanks are then rinsed with water and dried in the oven at 80 ° C for a short time.
- the clean PCB blanks can be wetted by water, which demonstrates a hydrophilic surface. The cleaning process is carried out less than 1 hour before the first monolayer production in order to minimize contamination.
- the PCB blanks were stored in a chamber with a controlled relative humidity of 55%.
- the cleaned PCB blanks are then immersed in a 3% 1-oxadadecanethiol / ethanol solution at room temperature for 15 minutes, rinsed with pure ethanol and then dried in an oven at 100 ° C. for 5 minutes.
- the coating process can be repeated any number of times.
- coated PCB blanks are then in 3% polystyrene Methacrylate-terminated cyclohexane solution dip-coated and dried in an oven at 120 ° C for 15 min.
- Copper-clad PCB blanks are cleaned in 20% phosphoric acid solution at room temperature for 5 min, rinsed in water and oven dried at 100 ° C for 5 min to form a hydrophilic surface.
- the pretreated PCB blanks were then immersed in a 1.5% 11-mercaptoundecylic acid-ethanol solution at room temperature for 15 minutes, rinsed with pure ethanol and then dried in an oven at 100 ° C. for 5 minutes.
- JP-63/005591 A Hata Hajime, Kinoshita Masashi, Kamagata Kazuo. JP-10/060207 A, Nishiguchi Hiroshi, Watanabe Toshio, Kitada Akira.
- EP-0 364 132 A Susumu Matsubara, Shuji Yoshida, Masahiko Minagawa, Daikichi Tachibana.
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006529421A JP2007505506A (ja) | 2003-05-13 | 2004-05-13 | 印刷回路板(pcb)を製造するためのブランクの被覆方法 |
EP04732543A EP1623608A2 (de) | 2003-05-13 | 2004-05-13 | Verfahren zur beschichtung von rohlingen zur herstellung von gedruckten leiterplatten (pcb) |
US10/556,514 US20080032109A1 (en) | 2003-05-13 | 2004-05-13 | Method for Coating Blanks for the Production of Printed Circuit Boards (Pcb) |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT0072603A AT412094B (de) | 2003-05-13 | 2003-05-13 | Verfahren zur beschichtung von rohlingen zur herstellung von gedruckten leiterplatten (pcb) |
ATA726/2003 | 2003-05-13 |
Publications (2)
Publication Number | Publication Date |
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WO2004103040A2 true WO2004103040A2 (de) | 2004-11-25 |
WO2004103040A3 WO2004103040A3 (de) | 2005-06-09 |
Family
ID=31192768
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/AT2004/000168 WO2004103040A2 (de) | 2003-05-13 | 2004-05-13 | Verfahren zur beschichtung von rohlingen zur herstellung von gedruckten leiterplatten (pcb) |
Country Status (5)
Country | Link |
---|---|
US (1) | US20080032109A1 (de) |
EP (1) | EP1623608A2 (de) |
JP (1) | JP2007505506A (de) |
AT (1) | AT412094B (de) |
WO (1) | WO2004103040A2 (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1568800A1 (de) * | 2004-02-25 | 2005-08-31 | Posco | Verfahren zum Korrosionschutz von Metallen unter Verwendung von Thiolverbindungen |
US7642104B2 (en) | 2005-07-07 | 2010-01-05 | Infineon Technologies Ag | Method for contacting semiconductor components with a test contact |
US8293724B2 (en) | 2007-10-12 | 2012-10-23 | The United States Of America, As Represented By The Secretary, Department Of Health And Human Services | Therapeutic applications of fatty acid amide hydrolase inhibitors |
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DE102004003784B4 (de) * | 2004-01-23 | 2011-01-13 | Ormecon Gmbh | Dispersion intrinsisch leitfähigen Polyanilins und deren Verwendung |
DE102004030388A1 (de) * | 2004-06-23 | 2006-01-26 | Ormecon Gmbh | Artikel mit einer Beschichtung von elektrisch leitfähigem Polymer und Verfahren zu deren Herstellung |
CA2662851A1 (en) * | 2006-09-13 | 2008-03-20 | Ormecon Gmbh | Article with a coating of electrically conductive polymer and precious/semiprecious metal and process for production thereof |
US8432036B2 (en) * | 2009-01-22 | 2013-04-30 | Aculon, Inc. | Lead frames with improved adhesion to plastic encapsulant |
DE102009023350A1 (de) | 2009-05-29 | 2010-12-02 | Osram Opto Semiconductors Gmbh | Elektronisches Bauelement und Verfahren zur Herstellung eines elektronischen Bauelements |
US8415252B2 (en) * | 2010-01-07 | 2013-04-09 | International Business Machines Corporation | Selective copper encapsulation layer deposition |
KR101593560B1 (ko) * | 2011-03-30 | 2016-02-15 | 후지필름 가부시키가이샤 | 프린트 배선기판 및 그 제조방법, 그리고 금속 표면 처리액 |
CN104937694B (zh) * | 2013-01-21 | 2018-12-28 | 卡姆特有限公司 | 在多组分表面上的表面预处理和液滴铺展控制 |
CN109252168B (zh) * | 2018-11-29 | 2024-01-12 | 珠海市智宝化工有限公司 | 一种高效活化酸性蚀刻液的装置及其方法 |
CN114885510B (zh) * | 2022-04-18 | 2023-07-04 | 安捷利美维电子(厦门)有限责任公司 | 一种减少铜面油墨黑点污染的方法 |
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JPS5834921A (ja) * | 1981-08-27 | 1983-03-01 | Nec Corp | 半導体装置の製造方法 |
US5281449A (en) * | 1990-08-09 | 1994-01-25 | Kansai Paint Company, Limited | Method of forming pattern coatings based on a radiation curable composition which contains a resin having both thioether and carboxyl groups |
JP2003066619A (ja) * | 2001-08-30 | 2003-03-05 | Fujitsu Ltd | レジストパターンの形成方法 |
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JPS6190492A (ja) * | 1984-10-11 | 1986-05-08 | 四国化成工業株式会社 | 銅スル−ホ−ルプリント配線板の製造方法 |
EP0364132A1 (de) * | 1988-09-29 | 1990-04-18 | Shikoku Chemicals Corporation | Verfahren zur Herstellung eines Konversionsüberzuges auf Oberflächen aus Kupfer oder Kupferlegierungen |
DE69329536T2 (de) * | 1992-03-02 | 2001-06-07 | Matsushita Electric Ind Co Ltd | Chemisch adsorbierter Film und Verfahren zur Herstellung desselben |
DE19944908A1 (de) * | 1999-09-10 | 2001-04-12 | Atotech Deutschland Gmbh | Verfahren zum Bilden eines Leitermusters auf dielektrischen Substraten |
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2003
- 2003-05-13 AT AT0072603A patent/AT412094B/de not_active IP Right Cessation
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2004
- 2004-05-13 JP JP2006529421A patent/JP2007505506A/ja active Pending
- 2004-05-13 WO PCT/AT2004/000168 patent/WO2004103040A2/de active Application Filing
- 2004-05-13 US US10/556,514 patent/US20080032109A1/en not_active Abandoned
- 2004-05-13 EP EP04732543A patent/EP1623608A2/de not_active Withdrawn
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JPS5834921A (ja) * | 1981-08-27 | 1983-03-01 | Nec Corp | 半導体装置の製造方法 |
US5281449A (en) * | 1990-08-09 | 1994-01-25 | Kansai Paint Company, Limited | Method of forming pattern coatings based on a radiation curable composition which contains a resin having both thioether and carboxyl groups |
JP2003066619A (ja) * | 2001-08-30 | 2003-03-05 | Fujitsu Ltd | レジストパターンの形成方法 |
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PATENT ABSTRACTS OF JAPAN Bd. 007, Nr. 115 (E-176), 19. Mai 1983 (1983-05-19) -& JP 58 034921 A (NIPPON DENKI KK), 1. März 1983 (1983-03-01) * |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1568800A1 (de) * | 2004-02-25 | 2005-08-31 | Posco | Verfahren zum Korrosionschutz von Metallen unter Verwendung von Thiolverbindungen |
US7642104B2 (en) | 2005-07-07 | 2010-01-05 | Infineon Technologies Ag | Method for contacting semiconductor components with a test contact |
US8293724B2 (en) | 2007-10-12 | 2012-10-23 | The United States Of America, As Represented By The Secretary, Department Of Health And Human Services | Therapeutic applications of fatty acid amide hydrolase inhibitors |
Also Published As
Publication number | Publication date |
---|---|
EP1623608A2 (de) | 2006-02-08 |
AT412094B (de) | 2004-09-27 |
ATA7262003A (de) | 2004-02-15 |
JP2007505506A (ja) | 2007-03-08 |
WO2004103040A3 (de) | 2005-06-09 |
US20080032109A1 (en) | 2008-02-07 |
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