CN104040026A - Formaldehyde-free electroless copper plating solution - Google Patents
Formaldehyde-free electroless copper plating solution Download PDFInfo
- Publication number
- CN104040026A CN104040026A CN201280049015.6A CN201280049015A CN104040026A CN 104040026 A CN104040026 A CN 104040026A CN 201280049015 A CN201280049015 A CN 201280049015A CN 104040026 A CN104040026 A CN 104040026A
- Authority
- CN
- China
- Prior art keywords
- acid
- electroless copper
- aqueous solution
- copper
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
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
- C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
- C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
- C23C18/31—Coating with metals
- C23C18/38—Coating with copper
- C23C18/40—Coating with copper using reducing agents
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemically Coating (AREA)
Abstract
The invention relates to an electroless aqueous copper plating solution, comprising a source of copper ions, a source of glyoxylic acid as reducing agent, and at least one polyamino disuccinic acid or at least one polyamino monosuccinic acid, or a mixture of at least one polyamino disuccinic acid and at least one polyamino monosuccinic acid as complexing agent, as well as to a method for electroless copper plating utilizing said solution and the use of the solution for the plating of substrates.
Description
Technical field
The present invention relates to a kind of electroless plating copper plating solution, utilize this solution to carry out the method for electroless copper and this solution for the purposes of plated substrate.
Background technology
Electroless plating is the controlled self-catalyzed deposition of continuous metal film under the help without external electrical supply.Can pre-treatment nonmetallic surface so that it has acceptability or catalytic to deposition.Whole or the selected portion on surface should be through pre-treatment.The main ingredient that electroless copper is bathed is mantoquita, complexing agent, reductive agent and as the alkali of the composition of optionally selecting, and additive, for example stablizer.The copper that complexing agent deposits for chelating and prevent that copper is from solution precipitation (being also oxyhydroxide and analogue form thereof).Make copper can be reduced agent utilization copper chelating, this reductive agent is converted into metallic forms by cupric ion.
Common electroless copper is bathed and is used formaldehyde as reductive agent.Formaldehyde is the most important and generally acknowledged reductive agent of common electroless copper plating method.1987, USEPA (U.S.Environmental Protection Agency) was categorized as possible mankind's carcinogens by formaldehyde.In June, 2004, (the International Agency for Research on Cancer of international cancer research institution; IARC) formaldehyde is categorized as to mankind's carcinogens.Therefore, do not developed and bathed to meet security and Occupational health requirement containing the electroless copper of formaldehyde.
US4,617,205 have disclosed a kind of composition of the electroless deposition for copper, and it comprises cupric ion, as the glyoxylate of reductive agent, and complexing agent, EDTA for example, it can form and be better than the copper complex formazan complex compound of oxalic acid with copper.
US7,220,296 have instructed a kind of chemical plating bath, and it comprises water miscible copper compound, oxoethanoic acid and complexing agent (can be EDTA).
US20020064592 has disclosed a kind of chemical plating bath, and it comprises cupric ion source, as oxoethanoic acid or the formaldehyde of reductive agent, and as EDTA, tartrate or the alkanolamine of complexing agent.
US20080223253 has disclosed a kind of chemical copper plating solution, and it comprises mantoquita, can be selected from formaldehyde, paraformaldehyde, oxoethanoic acid, NaBH
4, KBH
4, NaH
2pO
2, hydrazine, formalin, polysaccharide (such as glucose) and composition thereof reductive agent, and can be selected from the complexing agent of ethylenediamine tetraacetic acid (EDTA) (EDTA), hydroxyethylethylene diamine tri-acetic acid (HEDTA), CDTA, diethylene triamine pentacetic acid (DTPA) and four (2-hydroxypropyl) quadrol (below also referred to as " Quadrol ", the trade mark of Qi Wei BASF AG).
The defect of EDTA, HEDTA, four (2-hydroxypropyl) quadrol and other relevant complexing agent is to lack biological degradability.
The performance of copper plating solution is general unpredictable and mainly depending on the mol ratio of its component (especially complexing agent and reductive agent) and component thereof.
Summary of the invention
A target of the present invention is for providing the chemical copper plating solution that does not contain formaldehyde.
Another target is to provide has the chemical copper plating solution that improves performance (the copper sedimentation rate of for example improving).
Another target of the present invention is to adopt the chemical copper plating solution of the biodegradable complexing agent of copper.
Another target is containing the copper plating solution of formaldehyde, must not reach the standard of formaldehyde chemistry copper plating solution.It should be applicable to being applied to horizontal process and vertical process, and wherein the finished product are for example for high-end technology, as HDI (high density interconnect) PCB and IC substrate (IC=unicircuit, PCB=printed circuit board (PCB)).This solution also should be suitable for manufacturing indicating meter.
The invention provides a kind of chemical copper plating solution, it comprises
-cupric ion source,
-as the oxoethanoic acid of reductive agent, originate, and
-at least one poly-amino two succinic acid or at least one poly-amino monobutane diacid, or at least one poly-amino two succinic acid with at least one mixture that gathers amino monobutane diacid as complexing agent,
Wherein the mol ratio of complexing agent and cupric ion is in the scope of 1.1:1 to 5:1.
One or more above-mentioned targets are by chemical copper plating solution as claimed in claim 1 (being below abbreviated as " solution ") or complete by the favourable embodiment described in dependent claims and specification sheets.
The solution of claim 1 does not contain formaldehyde and demonstrates the copper sedimentation rate of improvement.Can reach 0.15-1.0 μ m/10min, 0.15-1.5 μ m/10min or the sedimentation rate of 0.15-2.0 μ m/10min even.
This advantage novel and that do not bathe containing the copper of formaldehyde is good bath performance, bathes stability, good spreadability, high sedimentation velocity and low bubbling trend.Crucial bath component formaldehyde substitutes with nontoxic reductive agent.
The mol ratio of poly-amino two succinic acid of complexing agent or poly-amino monobutane diacid and cupric ion causes the favourable character of plating solution, be that copper hydroxide precipitation is suppressed, bathes bubble formation in stability and copper facing process and is suppressed, as below and in working example further explained.
In an embodiment of the invention, the mol ratio of oxoethanoic acid and complexing agent is <4.6:1.In the present invention, show, with regard to spreadability for example, backlight and passivation, the quality that this mol ratio is deposited on substrate copper has Beneficial Effect.The further favourable mol ratio of oxoethanoic acid and complexing agent (being particularly EDDS) for≤4.5:1 ,≤4.2:1 ,≤4.0:1 ,≤3.8:1 ,≤3.6:1.The preferred lower limit of the mol ratio of oxoethanoic acid and complexing agent (being particularly EDDS) is 0.45:1 or 0.7:1,1:1 or 2:1.Therefore, the preferable range of the mol ratio of oxoethanoic acid and complexing agent (being particularly EDDS) is 0.45:1 to 4.5:1,0.45:1 to 4.2:1,0.45:1 to 4.0:1,0.45:1 to 3.8:1 or 0.45:1 to 3.6:1.Other preferable range is 1:1 to 4.5:1,1:1 to 4.2:1,1:1 to 4.0:1,1:1 to 3.8:1 or 1:1 to 3.6:1.Other preferable range of the mol ratio of oxoethanoic acid and complexing agent (being particularly EDDS) is 2:1 to 4.5:1,2:1 to 4.2:1,2:1 to 4.0:1,2:1 to 3.8:1 or 2:1 to 3.6:1.This ratio is relevant with the volumetric molar concentration amount of complexing agent, if use more than one complexing agents, means in this connection the total mol concentration amount of complexing agent.The volumetric molar concentration of oxoethanoic acid is preferably at least up to the volumetric molar concentration of copper in solution, more preferably higher.Therefore, the mol ratio of oxoethanoic acid and Cu preferably >=1:1, preferably >=1.5:1, more preferably >=2:1.
Poly-amino two succinic acid and poly-amino monobutane diacid demonstrate fabulous or even high biological degradability.Plating solution of the present invention is not containing ethylenediamine tetraacetic acid (EDTA) (EDTA), N'-(2-hydroxyethyl)-quadrol-N, N, N'-nitrilotriacetic (HEDTA) and four (2-hydroxypropyl) quadrol.
Solution of the present invention and method journey of the present invention are preferred for coated printed circuit board, chip carrier (chip carrier) and semiconductor wafer or also for being coated with any other circuit carrier and interconnection device.This solution is particularly for printed circuit board (PCB) and chip carrier, and semiconductor wafer, with by surface, groove, micro blindness hole (blind micro vias), through hole road (through hole vias) (through hole) and similar structures copper facing.
Particularly, solution of the present invention or method journey of the present invention be used on the surface of printed circuit board (PCB), chip, carrier, wafer and various other interconnection devices, groove, micro blindness hole, through hole and suitable deposited copper in structure.As used in the present invention, term " through hole road " or " through hole " are contained the through-hole passage of all kinds and are comprised so-called in silicon wafer " wearing silicon hole (through silicon via) ".
The metallization that is display application to the Another Application of solution imagination.Thus, copper is deposited on glass substrate especially, particularly on surface of plate glass.Compare with the metal sputtering method of using so far, the wet chemistry copper facing on glass substrate is deposited as favourable.Compare with sputter technology, the benefit that available wet chemistry plated deposition is realized be especially that the internal stress of glass substrate reduces and crookedly reduce, maintenance of the equipment minimizing, effective use of metal, material waste reduce.In addition, with solution of the present invention, reach the high copper sedimentation rate on glass substrate, especially using on the pretreated glass substrate of relatively less metal crystal seed.
Solution of the present invention is the aqueous solution.It is water that term " aqueous solution " means main liquid medium (it is the solvent in solution).Can add the liquid that other can be miscible with water, for example alcohol and other polar organic liquid, it can be miscible with water.
Solution of the present invention can, by all components is dissolved in water-based liquid medium, be preferable in water and prepare.
This solution contains cupric ion source, and it can be for example any water-soluble mantoquita.Copper can for example and be not limited to copper sulfate, cupric chloride, cupric nitrate, venus crystals, methanesulfonic copper ((CH
3o
3s)
2cu), copper hydroxide; Or its hydrate forms adds.
Use the electroless copper of above-mentioned reductive agent to bathe the preferably relatively high pH value of employing, conventionally between 11 and 14 or 12.5 and 14, preferably between 12.5 and 13.5 or between 12.8 and 13.3.PH value generally regulates by potassium hydroxide (KOH), sodium hydroxide (NaOH), lithium hydroxide (LiOH), ammonium hydroxide or tetramethylammonium hydroxide (TMAH).Therefore, solution can contain hydroxide ion source, for example and be not limited to one or more listed compound above.If if desired solution alkaline pH value and pH value not yet in alkaline range, are for example added oxyhydroxide source by other component.
Because the solvability of oxalic acid potassium is higher, so be especially preferably use potassium hydroxide.By oxidation, be used as the oxoethanoic acid of reductive agent and in solution, form oxalic acid root negatively charged ion.
Oxoethanoic acid is for cupric ion being reduced to the reductive agent of elemental copper.As used herein, term " oxoethanoic acid " comprises do not dissociate oxoethanoic acid and oxoethanoic acid radical ion.In solution, can there is do not dissociate oxoethanoic acid and oxoethanoic acid radical ion.The definite character of existing material (acid or salt) will be depending on pH.Identical consideration is applicable to other weak acid and weak base.
Term " oxoethanoic acid source " is contained oxoethanoic acid and allly can be turned in Transfer in Aqueous Solution the compound of oxoethanoic acid.In the aqueous solution, containing acid and its hydrate balance of aldehyde.The applicable source of oxoethanoic acid is two halogen acetic acids, and such as dichloro acetic acid, it will be hydrolyzed to glyoxylic acid hydrate in water-bearing media.The substituting source of oxoethanoic acid is bisulfite adduct, as is hydrolyzable ester or other acid derivative.Bisulfite adduct can be added in composition or then and there and form.Bisulfite adduct can be made by glyoxylate and hydrosulphite, sulphite or metabisulphite.
Can add if desired one or more other reductive agents, for example diphosphanetetroic acid, oxyacetic acid or formic acid, or the salt of above-mentioned acid.Yet solution of the present invention is not containing formaldehyde.Therefore, this solution is not containing formaldehyde.Other reductive agent is preferably and serves as reductive agent, but the reagent (referring to US7,220,296 the 4th hurdle 20-43 are capable and 54-62 is capable) that can not use as unique reductive agent.In this meaning, another reductive agent is also referred to as " toughener ".
Poly-amino two succinic acid are the compound with two or more nitrogen-atoms, and wherein 2 nitrogen are binding on succinic acid (or salt) group, and preferably only two nitrogen-atoms are connected with a succinic acid (or salt) group separately.As used herein, term succinic acid comprises its salt.This compound has at least 2 nitrogen-atoms, and due to the business availability of amine, preferably has and be no more than approximately 10 nitrogen-atoms, more preferably no more than approximately 6 nitrogen-atoms, 2 nitrogen-atoms most preferably.The nitrogen-atoms that is not connected with succinic acid part most preferably replaces through hydrogen atom.Succinic acid group is more preferably endways on nitrogen-atoms, and most preferably, this nitrogen also has hydrogen substituting group separately.End means first or last nitrogen-atoms being present in compound, no matter and other substituting group why.Another of terminal nitrogen is defined as the primary amine nitrogen before connecting succinic acid part.After connecting succinic acid part, terminal nitrogen is transferred to secondary amine nitrogen.Because the steric hindrance of two succinic acid groups on a nitrogen, preferably only has a this group so have each nitrogen of succinic acid group.There are all the other keys on the nitrogen of succinic acid group preferably by hydrogen or alkyl or alkylidene group (straight chain, branching or ring-type, comprise the ring texture that engages an above nitrogen-atoms or engage an above key of single nitrogen-atoms, be preferably straight chain) or this group (all preferably there is 1 to 10 carbon atom, more preferably 1 to 6,1 to 3 carbon atom most preferably, but most preferably be hydrogen) with ether or thioether keyed jointing fill up.Preferred alkyl is methyl, ethyl and propyl group.Nitrogen-atoms is more preferably by alkylidene group binding, this alkylidene group preferably has 2 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, even more preferably 2 to 8,2 to 6 carbon atoms most preferably separately, is also ethylidene, propylidene, butylidene, pentylidene or hexylidene.Poly-amino two succinic acid compounds preferably have at least about 10 carbon atoms and preferably have approximately 50 at the most, more preferably approximately 40, approximately 30 carbon atoms at the most most preferably at the most.Term " succinic acid " is in this article for acid and salt thereof; Salt comprises metallic cation (for example potassium, sodium) and ammonium or amine salt.
Be applicable to put into practice poly-amino two succinic acid of the present invention for being unsubstituted (preferably) or replacing through inertia, also through can desirably disturbing the active group of poly-amino two succinic acid in selected application to replace.This inert substituent comprises alkyl (preferably having 1 to 6 carbon atom); Aryl, comprises arylalkyl and alkylaryl (preferably having 6 to 12 carbon atoms), wherein alkyl be preferably and in alkyl methyl and ethyl for preferably.
Inert substituent should be in any part of molecule, preferably on carbon atom, more preferably on alkylidene group (for example, at the alkylidene group between nitrogen-atoms or between hydroxy-acid group), most preferably on the alkylidene group between nitrogen groups.
Preferred poly-amino two succinic acid comprise quadrol-N, N'-bis-succinic acid (EDDS), diethylenetriamine-N, N " bis-succinic acid, Triethylenetetramine (TETA)-N, N " '-bis-succinic acid, 1, 6 hexanediamine N, N'-bis-succinic acid, tetren-N, N " "-bis-succinic acid, 2-hydroxy propylidene-1, 3-diamines-N, N'-bis-succinic acid, 1, 2 propylene diamine-N, N'-bis-succinic acid, 1, 3-propylene diamine-N, N " bis-succinic acid, cis cyclohexane diamine-N, N'-bis-succinic acid, trans cyclohexane diamines-N, N'-bis-succinic acid and ethylene glycol bis (2-amino-ethyl ether)-N, N'-bis-succinic acid (ethylenebis (oxyethylenenitrilo)-N, N'-disuccinic acid).Preferred poly-amino two succinic acid are quadrol-N, N'-bis-succinic acid.
This poly-amino two succinic acid can be such as the process preparation disclosing in U.S. patent 3,158,635 (mode of quoting is in full incorporated herein) by people such as Kezerian.The people such as Kezerian disclose MALEIC ANHYDRIDE (or ester or salt) are reacted under alkaline condition with the polyamine corresponding to required poly-amino two succinic acid.This reaction obtains many optical isomers, for example, because there are two unsymmetrical carbons in quadrol two succinic acid, so quadrol obtains three kinds of optical isomers [R, R], [S with reacting of MALEIC ANHYDRIDE, S] and the mixture of [S, R] quadrol two succinic acid (EDDS).These mixtures are used with form of mixtures, or by the method separation in currently available technology to obtain required isomer.Or, [S, S] isomer by such as the acid of L-Aspartic acid with such as 1, the compound of 2-ethylene dibromide reacts to prepare, as Neal and Rose, " Stereospecific Ligands and Their Complexes of Ethylenediaminedisuccinic Acid ", Inorganic Chemistry, the 7th volume, (1968), described in 2405-2412 page.
Poly-amino monobutane diacid is connected in the compound of a nitrogen-atoms for having at least two nitrogen-atoms and succinic acid (or salt) part.This compound preferably has at least 2 nitrogen-atoms and due to the business availability of amine, preferably have be no more than approximately 10 nitrogen-atoms, more preferably no more than approximately 6,2 nitrogen-atoms most preferably.All the other nitrogen-atoms (not being connected with the atom of succinic acid part) preferably replace through hydrogen atom.Although succinic acid part can be connected in any amine, Dante diacid group is preferably connected in terminal nitrogen atom.End means first or last amine existing in compound, no matter and other substituting group how.Another of terminal nitrogen is defined as primary amine nitrogen, connects subsequently succinic acid part.After connecting succinic acid part, terminal nitrogen is transferred to the nitrogen of secondary amine.There are all the other keys on the nitrogen of succinic acid group preferably by hydrogen or alkyl or alkylidene group (straight chain, branching or ring-type, comprise the ring texture that engages an above nitrogen-atoms or engage an above key of single nitrogen-atoms, be preferably straight chain) or this group (all preferably there is 1 to 10 carbon atom, more preferably 1 to 6,1 to 3 carbon atom most preferably, but most preferably be hydrogen) with ether or thioether binding fill.Preferred alkyl is methyl, ethyl and propyl group.Nitrogen-atoms is generally by alkylidene group binding, and this alkylidene group has 2 to 12 carbon atoms, preferably 2 to 10 carbon atoms, more preferably 2 to 8 and 2 to 6 carbon atoms most preferably separately, is also ethylidene, propylidene, butylidene, pentylidene or hexylidene.Poly-amino monobutane diacid compound preferably has at least about 6 carbon atoms and preferably has approximately 50 at the most, more preferably approximately 40 and approximately 30 carbon atoms at the most most preferably at the most.Be applicable to put into practice poly-amino monobutane diacid of the present invention for be unsubstituted (preferably) or as replaced through inertia above as described in poly-amino two succinic acid compounds.
Preferred poly-amino monobutane diacid comprises quadrol monobutane diacid, diethylenetriamine monobutane diacid, Triethylenetetramine (TETA) monobutane diacid, 1,6-hexanediamine monobutane diacid, tetren monobutane diacid, 2-hydroxy propylidene-1,3-diamines monobutane diacid, 1,2-propylene diamine monobutane diacid, 1,3-propylene diamine monobutane diacid, cis cyclohexane diamine monobutane diacid, trans cyclohexane diamines monobutane diacid and ethylene glycol bis (2-amino-ethyl ether) monobutane diacid.Preferred poly-amino monobutane diacid is quadrol monobutane diacid.
This poly-amino monobutane diacid can such as by people such as Bersworth in U.S. patent 2,761,874 (its disclosure is incorporated herein by reference) and as Jpn.Kokai Tokkyo Koho JP57, prepared by the method disclosing in 116,031.Generally speaking, the people such as Bersworth disclose Alkylenediamine and two alkylene triamine under mild conditions are reacted with the maleate under mild conditions (in alcohol), obtain the amido derivative of the aspartic acid of N-alkyl replacement.This reaction obtains the mixture of R isomer and S isomer.
In one embodiment, when solution contains poly-amino two succinic acid and gathers the mixture of amino monobutane diacid, poly-amino two succinic acid are preferably identical with the poly-amino substituting group of poly-amino monobutane diacid.Therefore for example, if poly-amino two succinic acid are quadrol-N, N'-bis-succinic acid, polyamine monobutane diacid is quadrol monobutane diacid.
In a preferred embodiment, by quadrol-N, N'-bis-succinic acid (EDDS) are as complexing agent.EDDS is preferred complexing agent because of its high biological degradability.Containing other electroless copper of biodegradable complexing agent (as tartrate), bathe and conventionally use toxicity metallic nickel altogether.Found to avoid in the present invention toxicity metal altogether.Therefore, solution of the present invention is not total to metal containing toxicity.Solution of the present invention is preferably without nickel.
The present inventor has found to obtain in comprising the solution of the present invention of oxoethanoic acid and EDDS the copper sedimentation rate of significantly improving.Because in adopting the comparative example of formaldehyde, when formaldehyde-EDDS combination is compared with formaldehyde-EDTA, copper deposition is not improved or is only slightly improved, and institute is as unpredictable consequence.
Term " EDDS " comprises racemize EDDS or its all optically active isomers, such as (S, S)-EDDS, and salt and derivative.This term preferably means (S, S)-EDDS or its salt.EDDS can be prepared by the method for PCT/GB94/02397.In solution, depending on pH, can there are quadrol two succinic acid and quadrol two succinic ions.
In one embodiment, the cupric ion that solution of the present invention contains following concentration, complexing agent (being preferably EDDS) and oxoethanoic acid:
Cu ion: 1-5 g/l is corresponding to 0.016-0.079mol/l
Complexing agent: 5-50g/l is corresponding to 0.034-0.171mol/l
Oxoethanoic acid: 2-20g/l is corresponding to 0.027-0.270mol/l
Solution of the present invention more preferably contains cupric ion, complexing agent (being preferably EDDS) and the oxoethanoic acid of following concentration:
Cu ion: 2-3g/l is corresponding to 0.031-0.047mol/l
Complexing agent: 20-40g/l is corresponding to 0.068-0.137mol/l
Oxoethanoic acid: 2-20g/l is corresponding to 0.027-0.270mol/l
In the present invention, the mol ratio of complexing agent (meaning in this connection complexing agent total amount, also even use more than one complexing agents, is the mole number sum of all complexing agents) and cupric ion is in 1.1:1 to 5:1, more preferably in the scope of 1.5:1 to 5:1.Shown when using this mol ratio, also, when complexing agent (being particularly EDDS) is when with respect to the excessive volumetric molar concentration use of copper, solution of the present invention has better properties.In the present invention, when by oxoethanoic acid when the reductive agent, at least the mol ratio of 1.1:1 is essential by complex copper ion to demonstrate complexing agent (being particularly EDDS) and copper.Mol ratio <1:1 causes copper hydroxide precipitation and copper facing may not occur.On the other hand, the mol ratio of >5:1 can cause bath unstable and the high bubble formation on substrate surface in copper facing process.
In another embodiment, complexing agent (meaning in this connection complexing agent total amount) is 2:1 to 5:1, more preferably 3:1 to 5:1 with the mol ratio of cupric ion.If stirring copper between depositional stage bathes, preferably use air agitation, and when also using another reductive agent (also referred to as " toughener ") except oxoethanoic acid, wherein this another reductive agent is preferably selected from oxyacetic acid, diphosphanetetroic acid or formic acid, most preferably be oxyacetic acid, this example is especially favourable.
Solution of the present invention can comprise and not necessarily comprise other component, for example stablizer, tensio-active agent, additive (as rate-controlling additive), crystal grain macro additive, pH value buffer reagent, pH value conditioning agent and toughener.This other component is for example described in in Publication about Document (mode of quoting is in full incorporated to): US4,617,205 (being particularly the disclosure that the 6th hurdle the 17th walks to the 7th hurdle the 25th row), US7,220,296 (being particularly that the 4th hurdle the 63rd walks to the 6th hurdle the 26th row), US2008/0223253 (particularly referring to paragraph 0033 and 0038).
Stablizer is for to make the stable compound of chemical plating solution for less desirable outer plating (outplating) in bulk solution.Term " plating outward " means nonspecific and/or uncontrolled copper deposition.The reduction of copper (II) should only occur but not in whole bath, be not specific on required substrate surface.Stabilization function can be for example by serve as the material (compound that for example contains sulphur or other chalkogenide) of catalyzer poison or by forming copper (I) complex compound, the compound that suppresses to form thus cupric oxide (I) realizes.
Applicable stablizer is that (being not limited to) dipyridyl (2,2'-dipyridyl, 4,4' dipyridyl), phenanthroline, sulfydryl-benzothiazole, thiocarbamide or derivatives thereof (as diethyl thiourea), prussiate are (as NaCN, KCN, K
4[Fe (CN)
6]), thiocyanate-, iodide, thanomin, sulfydryl-benzotriazole, Na
2s
2o
3, polymkeric substance (as polyacrylamide, polyacrylate(s), polyethylene glycols or polypropylene glycols and multipolymer thereof), wherein 2,2'-dipyridyl (being abbreviated as " DP "), diethyl-thiocarbamide, K
4[Fe (CN)
6], NaCN and sulfydryl-benzothiazole be to be especially applicable to.
In one embodiment, mainly due to environment and Occupational health reason, stablizer is selected from the stablizer of cyanide-free.Therefore, the preferred cyanide-free of solution of the present invention.In this connection, 2,2'-dipyridyl is preferred stablizer.Dipyridyl preferably adds with the amount of 1-10mg/l.
European application EP1876262 discloses a kind of electroless copper and bathes, and it contains one or more thiocarboxylic acid as essential component.The thio-compounds of mentioning in EP1876262 comprises the compound with formula HS-(CX1) r-(CHX2) s-COOH, wherein X1 be-H or-COOH; X2 is-H or-SH; R and s are positive integer, and wherein r is 0 to 2, or 0 or 1; And s is 1 or 2.The particular instance of the thio-compounds of mentioning in EP1876262 is thioglycolic acid, propane thioic acid, mercaptosuccinic acid and dithio two succinic acid.According to EP1876262, this thiocarboxylic acid and oxoethanoic acid and salt thereof can be compatible and by preventing from forming the copper composition stability that cupric oxide makes electroless plating.According to EP1876262, the essential minimum of thio-compounds is 0.01ppm.In the present invention, demonstrate in EP1876262 usually and the thiocarboxylic acid component of specifically mentioning avoids using or at least lower than in EP1876262, mention limit time, the better performances that electroless copper is bathed.Can exist trace as in EP1876262 usually and the thiocarboxylic acid of specifically mentioning, prerequisite is for this amount is lower than 0.01ppm.Yet, preferably thiocarboxylic acid is not added in solution of the present invention, i.e. this bath does not contain in EP1876262 usually and any thiocarboxylic acid of specifically mentioning yet.
In another aspect, the present invention relates to a kind of electroless copper plating method, the method comprises makes substrate contact with chemical copper plating solution as above.
For example, substrate can flood or be immersed in solution of the present invention.In the method, can be by the whole surface of substrate or only selected portion copper facing.
Preferably stir during use solution.Particularly, can use work stirring and/or agitation.Preferably stir the air agitation that kind is solution.Air agitation can be by realizing air bubbling through the solution in using.
The method will be carried out one section of grace time to obtain the settling of desired thickness, and desired thickness again will be depending on application-specific.
A contemplated application of the present invention will be particularly useful for preparing printed circuit board (PCB).What according to the electroless deposition of the copper of the inventive method, especially can be used for hole in printed circuit board (PCB), surface, groove, blind microchannel wears plating (through-plating).Bilateral or multi-ply wood (rigidity or flexible) can carry out plating by means of the present invention.
Method journey of the present invention is applicable to providing thickness in the scope of 0.1 μ m to 25 μ m, preferably the copper deposit of the electroless plating between 0.25 μ m and 3 μ m.
The substrate that is generally used for printed circuit board (PCB) manufacture is the most often epoxy resin or epoxy-glass composite.But can use other material, be in particular resol, tetrafluoroethylene (PTFE), polyimide, polyphenylene oxide, two maleic acid triazine-resin (bismaleintriazine-resins, BT resin), cyanate and polysulfones.
Except applying the method in printed circuit board (PCB) manufacture, also can find that the method is generally applicable to plate non-conductive substrate, comprise plastics, such as acronitrile-butadiene-styrene (ABS) and polycarbonate; Pottery and glass.
In an embodiment of the inventive method, the method is at 20-60 ℃, preferably 20-55 ℃, more preferably 20-50 ℃, even more preferably 20-45 ℃ and most preferably carry out at the temperature within the scope of 20-40 ℃.Because use the solution based on formaldehyde of current technology, for good plating usefulness, especially, for enough copper sedimentation rates, must there is comparatively high temps, so this embodiment is very favourable.
The surface of the copper-plated substrate of wish, is also substrate surface, especially nonmetallic surface, can carry out pre-treatment (for example US4, described in 617,205 the 8th hurdles) by the method within the scope of this area, so that it has higher acceptability or autocatalysis for copper deposition.Whole or the selected portion on surface can be through pre-treatment.Yet, not all essential pre-treatment and optic placode and surperficial kind and determine in each situation.In pre-treatment, can make substrate sensitization, subsequently sedimentation chemistry copper facing thereon.This measure can for example, by making catalytic metal (such as precious metal, palladium) be adsorbed on substrate surface and realize.
Preprocessing process is mainly depending on parameter (as the required character on substrate, required application and copper surface).
Exemplary and the non-limiting preprocessing process that is particularly useful for printed circuit board (PCB) laminates and other applicable substrate can comprise following steps:
A) substrate is contacted with activator solution, this solution contains colloidal state or ionic catalytic metal, such as precious metal, is preferably palladium, makes the substrate surface tool catalytic that becomes,
And optionally, if especially activator contains ionic catalysis metal,
B) substrate is contacted with reductive agent, wherein the metal ion of ion activation agent is reduced to metal element,
Or, if activator contains colloidal state catalytic metal,
C) substrate is contacted with accelerator, wherein for example, by the component autocatalysis metal removal of colloid (protective colloid).
Preferably above-mentioned steps a) can optionally take before other step that any combination carries out as:
I. clean and adjusting substrate adsorbs to increase.With sanitising agent, remove organism and other resistates.Sanitising agent also can contain prepares for activation step surface, also strengthens other material (conditioning agent) that catalyzer adsorbs and produce more uniform activating surface.
Ii. this substrate of etching is with from copper surface, especially the internal layer from hole removes oxide compound.This can be undertaken by the etch system based on persulphate or superoxide.
Iii. make substrate contact with preimpregnation solution (such as hydrochloric acid soln or sulphuric acid soln), in this preimpregnation solution, optionally contain an alkali metal salt (such as sodium-chlor).Preimpregnation liquid is in order to protect activator avoid bringing into (drag-in) and pollute.
In the preprocessing process of another kind, adopt permanganate etching step.Enclose and described the so-called decontamination process (Desmear process) of using permanganate etching step in example.Decontamination process can combine with above-mentioned steps.Particularly, decontamination process can be in the step of above-mentioned preprocessing process a) before, or at execution step i)-iii) in a step or multistep in the situation that at above-mentioned steps i)-iii) carry out before.Also can carry out decontamination process and carry out alternative steps i) and ii).
In being particularly suited for the metallization of display application and the metallized preprocessing process of glass substrate, only make surface contact with preimpregnation solution and activator solution, then contact with solution of the present invention.Before pre-soak step, contact the step for optionally selecting with cleaning liquor and adhesiving reinforcing agent, it can carry out in advance.
The following step of can usining before copper facing carries out through being usually used in another process of glass substrate: the glass surface of wish plating represents the metallics as crystal seed.Metallics can bring on surface by sputter technology.The serve as reasons particle of following formation of exemplary crystal seed: copper, titanium, molybdenum, zirconium, aluminium, chromium, tungsten, niobium, tantalum or its mixture or alloy.Another crystal seed can be metal oxide, or mixed metal oxide, for example tin indium oxide.This process also can be used for plastic base, the substrate for example being made by polyethylene terephthalate.
Make this pretreated glass surface and the activator solution contact that contains ionic catalysis metal (such as precious metal, being preferably palladium), make the surface tool catalytic that becomes.By seed metal, make ionic catalysis metallic reducing on surface.In this process, can omit and add another reductive agent.This process is particularly useful in the copper facing for the glass substrate of display application.
Exemplary preprocessing process or its one step be the substituting preprocessing process of one-tenth capable of being combined if desired.
In another aspect, the present invention relates to chemical copper plating solution as above for the purposes of the following thing of plating: printed circuit board (PCB), wafer, ic substrate, MID (mold interconnecting device, molded interconnect device) assembly, indicating meter is (such as liquid-crystal display, TFT indicating meter, plasma display, electroluminescent display (ELD) and Electrochromic Display (ECD), particularly for the indicating meter of following thing: electronic installation or TV, display module, flat panel sensor, such as x-ray imaging device), or plastic paste, such as the plastic paste for functional or ornamental object.
Now by following instance, the present invention is described in more detail.Set forth this example with explanation the present invention, but should not be considered as limiting the present invention.
Accompanying drawing explanation
Fig. 1 is for the step of the decontamination multi stage process of clean surface.
Fig. 2 is for the step of through hole plating (through hole) process that activates.
Fig. 3, for the reference sample of measurement backlight, shows the result of D1 to D10.
Copper thickness when Fig. 4 is used the bath with different complexing agents on glass substrate.
Example
method
Method backlight:
The copper-plated spreadability of electroless plating in through hole can be used industrial standards test backlight (Backlight Test) to assess, wherein the test piece of electroless plating is cut, the region that the box lunch of take not exclusively covers when intense light source is inspected is bright spot [US2008/0038450A1] after testing.
The quality of copper deposit is measured by the light quantity of observing under conventional opticmicroscope.
The result of measurement backlight provides with D1 to D10 scale, and wherein D1 means the poorest result and D10 and means the best and select result.Fig. 3 shows the reference sample that shows D1 to D10 result.
1. example
Bathe and form
Form table
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 2-3g |
| Biodegradable complexing agent (EDDS) | 20-25g |
| Alkali (KOH) | 20-40g |
| Stablizer (dipyridyl) | 0.001-0.005g |
| Reductive agent (oxoethanoic acid) | 6.4-24g |
Service temperature: 38-50 ℃
Sedimentation rate: approximately 0.6 μ m/10min.
Job description
In this example, in common decontamination process, process test sample book with lancing door wall surface and internal layer copper surface.In addition, make resin surface roughening to reach good copper binding property.
Decontamination process is multi stage process, and its step is showed in Fig. 1.
Swelling agent is made by ORGANIC SOLVENT MIXTURES.During this step, remove and bore stain (drill smear) and other impurity.The high temperature of 60-80 ℃ promotes swelling agent infiltration, thereby produces the surface of expanding.Therefore, with after-applied permanganate solution, can produce compared with vigorous erosion.Afterwards, reducing solution (reaction control agent) removes the Manganse Dioxide producing during permanganate step from surface.
In PTH (plated-through-hole, plating through hole) process, prepared electrically nonconducting material and deposited for copper.Fig. 2 shows the activation step of PTH process.
Sanitising agent is in order to remove organism and to regulate surface for follow-up activation step.
Etch cleaned agent removes oxide compound from the surface of Kong Zhongtong internal layer.Material as etch cleaned agent is selected from the mixture of sulfuric acid and hydrogen peroxide, or is selected from peracetic dithionite or is selected from permonosulphuric acid salt.Etch cleaned liquid is except also containing additive and/or stablizer containing etch composition.
With palladium activation panel and hole surface, be to carry out in the activator that contains colloidal state or ionic catalytic metal (such as precious metal, being preferably palladium), make the surface tool catalytic that becomes.In a possible configuration, activator contains the palladium ion by organic ligand complexing.There is the preimpregnation liquid (Predip) of prefix should protect activator in order to avoid bring into and pollute.
The final step of reactivation process is reductive agent (Reducer).Herein, palladium ion is reduced to the element palladium with high catalytic activity.After reductive agent step, with solution of the present invention, carry out electroless copper deposition.Reductive agent and ionic metal compound combination are as activator.It adopts as the reductive agent of hypophosphite, hydroborate, amido borohydride.
For electroless copper deposition, by the order with general introduction in table 1, bath component is added in suitable quantity of water and produces and bathe formation.Use air agitation.Service temperature changes between 38-50 ℃.And depositing time is through being set as 10-60 minute to reach required copper thickness.
Bathe feature
Sedimentation velocity (for example, to FR4 material (Matsushita MC100EX) measured): approximately 0.6 μ m/10min.
Bubbling trend (test material: from the ABF GX-92 of Ajinomoto): low or nothing
Spreadability (FR4 and GX-92): good
Color (FR4 and GX-92): orange red
FR4 test covering copper to through hole is backlight.
Plating example
Make test panel experience whole decontamination process (following table).
Decontamination process
| Decontamination step | Immersion time [minute] |
| Swelling agent | 5 |
| Permanganate | 10 |
| Reduction conditioning agent | 5 |
Reactivation process based on ion activation agent system:
Reactivation process
| Activator step | Immersion time [minute] |
| Sanitising agent | 4 |
| Etch cleaned agent | 1 |
| Preimpregnation liquid | 1 |
| Activator | 4 |
| Reductive agent | 3 |
The formation example that copper is bathed is described in following table.
Bathe the example forming
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 3g(0.047mol) |
| Biodegradable complexing agent: (S, S)-EDDS | 25g(0.085mol) |
| Alkali: KOH | 23g |
| Stablizer: 2,2'-dipyridyl | 0.003g |
| Reductive agent: oxoethanoic acid | 10g(0.135mol) |
Service temperature: 38 ℃
Sedimentation rate: 0.6 μ m/10min.
Bubbling trend: nothing
Spreadability: good
D8 backlight
Color: orange red
2. comparative example: oxoethanoic acid and HEDTA or oxoethanoic acid and some biodegradable complexing agent comparative example 2.1:HEDTA (N'-(2-hydroxyethyl)-quadrol-N, N, N'-nitrilotriacetic)
Bathe and form
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 2g |
| Complexing agent: HEDTA | 15g |
| Alkali: KOH | 11.2g |
| Stablizer: 2,2'-dipyridyl | 0.006g |
| Reductive agent: oxoethanoic acid | 7.4g |
Service temperature: 45 ℃
Sedimentation rate: 0.5 μ m/10min
Backlight: D7
Bathe stability: good
Spreadability: good
Color: orange red
Shortcoming: abiotic degradable complexing agent
Comparative example 2.2: biodegradable Sorbitol Powder
Bathe and form
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 3g |
| Biodegradable complexing agent: Sorbitol Powder | 25g |
| Alkali: KOH | 11.2g |
| Stablizer: 2,2'-dipyridyl | 0.004g |
| Reductive agent: oxoethanoic acid | 6.7g |
Service temperature: 60 ℃
Sedimentation rate: 0.3 μ m/10min
Backlight: D8
Bathe stability: low
Spreadability: good
Color: orange red
Shortcoming: low deposition rate
Comparative example 2.3: biodegradable Seignette salt
Bathe and form
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 2.5g |
| Biodegradable complexing agent: Seignette salt | 90g |
| Alkali: KOH | 6g |
| Stablizer: 2,2'-dipyridyl | 0.004g |
| Reductive agent: oxoethanoic acid | 5g |
Service temperature: 38 ℃
Sedimentation rate: 0.3 μ m/10min
Backlight: D8-D9
Bathe stability: low
Bubbling trend: low
Spreadability: good
Color: orange red
Shortcoming: need high complexing agent concentration and sedimentation rate low
Comparative example 2.4: biodegradable gluconic acid
Bathe and form
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 1.5g |
| Biodegradable complexing agent: gluconic acid | 18g |
| Alkali: KOH | 16g |
| Stablizer: 2,2'-dipyridyl | 0.008g |
| Reductive agent: oxoethanoic acid | 7.4g |
Service temperature: 50 ℃
Sedimentation rate: 0.4 μ m/10min
Backlight: D4-D5
Bathe stability: extremely low
Spreadability: bad
Color: micro-deeply orange red
Shortcoming: bad copper deposition and extremely low bath are active
General introduction:
When oxoethanoic acid is used as to reductive agent, common biodegradable complexing agent (as tartrate) can not meet again bathes requirement.The comparative biodegradable complexing agent containing oxoethanoic acid of test above shows low deposition rate and/or needs high complexing agent concentration.Other biodegradable complexing agent of testing does not show copper deposition at all or demonstrates bad result about spreadability, sedimentation velocity and bubbling trend.On the contrary, (S, S)-quadrol-N, N'-bis-succinic acid ((S, S)-EDDS) are biodegradable and meet the requirement of electroplating industry.The solution of the present invention that contains EDDS is characterised in that its good usefulness, good spreadability, high sedimentation velocity and low bubbling trend of bathing.Due to the strong complexation property of EDDS, the stability that copper of the present invention is bathed is than much better with other biodegradable complexing agent.
3. example: EDDS and EDTA contain the comparison of different reductive agents
3.1 contain oxoethanoic acid as the example of reductive agent
3.1.1 bathe and form 1: containing the solution of the present invention of oxoethanoic acid/EDDS
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 3g |
| Complexing agent: EDDS | 30g |
| Alkali: KOH | 7.2g |
| Stablizer: 2,2'-dipyridyl | 0.003g |
| Reductive agent: oxoethanoic acid | 8g (about 0.1mol/l) |
Service temperature: 38 ℃
Sedimentation rate: 0.8 μ m/10min
Backlight: D6
Bathe stability: good
Spreadability: good
Color: orange red
Bubbling: without bubble
3.1.2 bathe and form 2: containing the comparative example of oxoethanoic acid/EDTA
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 3g |
| Complexing agent: EDTA | 20g |
| Alkali: KOH | 7.2g |
| Stablizer: 2,2'-dipyridyl | 0.003g |
| Reductive agent: oxoethanoic acid | 8g (about 0.1mol/l) |
Service temperature: 38 ℃
Sedimentation rate: 0.4 μ m/10min
Backlight: D4
Bathe stability: good
Spreadability: bad, can be observed passivation
Color: micro-deeply orange red
Bubbling: nothing
Result:
When comparative example 3.1.1 and 3.1.2, about the copper sedimentation rate under identical plating condition, the copper plating solution that contains EDDS is than the fast twice of the bath that contains EDTA.In addition, with EDDS, reach preferred spreadability.
3.2 using the comparative example of formaldehyde as reductive agent
3.2.1 bathe and form 3: containing the comparative example of formaldehyde/EDDS
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 3g |
| Complexing agent: EDDS | 30g |
| Alkali: KOH | 7.2g |
| Stablizer: 2,2'-dipyridyl | 0.003g |
| Reductive agent: formaldehyde | 5g (about 0.1mol/l) |
Service temperature: 38 ℃
Sedimentation rate: 1.1 μ m/10min
Backlight: D7
Bathe stability: good
Spreadability: good
Color: orange red
Bubbling: without bubble
3.2.2 bathe and form 4: containing the comparative example of formaldehyde/EDTA
| Bathe component | The concentration of every 1l |
| Cupric ion (Cu 2+) | 3g |
| Complexing agent: EDTA | 20g |
| Alkali: KOH | 7.2g |
| Stablizer: 2,2'-dipyridyl | 0.003g |
| Reductive agent: formaldehyde | 5g (about 0.1mol/l) |
Service temperature: 38 ℃
Sedimentation rate: 0.9 μ m/10min
Backlight: D6
Bathe stability: low
Spreadability: bad, slight passivation
Color: micro-deeply orange red
Bubbling: be
Result:
Bath containing EDDS/ formaldehyde demonstrates than the slightly high sedimentation rate of bath containing EDTA/ formaldehyde.But when EDTA is substituted by EDDS (referring to example 3.1.1 and 3.1.2), the increase of sedimentation rate is than much lower with oxoethanoic acid.Therefore,, in containing the bath of formaldehyde, EDDS can be equivalent to or be better than a little EDTA.Yet, using oxoethanoic acid as reductive agent, EDDS shows the result (sedimentation rate increase approximately 100%) more much better than EDTA, this cannot predict in view of background technology.
4. example: use the complexing agent EDDS of different concns and the experiment of copper
The variation of mol ratio EDDS:Cu
Test result
Sedimentation rate: 0.6 μ m/10min
The mol ratio EDDS:Cu of at least essential 1.1:1 is with the cupric ion in complexing basic solution.Mol ratio <1.1:1 causes copper hydroxide precipitation.Therefore, may be without copper facing.
Mol ratio >5:1 causes the high bubbling trend of bathing on unstable and PCB material.Deposited colors for dark orange red and backlight be under the desirable value of D7.
Can be with finding uncontrolled copper deposition on beaker after bathing 6 (EDDS:Cu that mol ratio is 6:1) electroless copper.Bath stability is inadequate.
5. example: there is different oxoethanoic acids: the coating solution of EDDS mol ratio
The different mol ratio of EDDS and oxoethanoic acid in the bath of test electroless copper, as shown in following table.
Bathe and form:
The volumetric molar concentration of Cu, complexing agent and reductive agent and quality
Test panel experiences whole decontamination process (table 2) and (table of the reactivation process based on ion activation agent system
3), described in example 1.
Following parameter is applied to the electroless plating in electroless copper bath:
-T=38℃
-illusory plating (Dummy plating): 10-15 minute
-exposure duration: 10 minutes
-test material: outside the GX-92 (short decontamination: 2', 4', 4') and FR4 that have described in example 1, also use the test panel of being made by following material.
ABS (short decontamination: 2', 4', 2') is for test coverage and passivation;
R1755C (decontamination: 5', 10', 5') is for test backlight.
In following table, show the result of deposition test.
| Bathe numbering | A | B | C | D |
| Bathe stability (continuing one) | Stable | Stable | Stable | Stable |
| Spreadability | 100% | 50% | 0% | 0% |
| Backlight | D7-D8 | D8-D9 | n/a | n/a |
| Passivation | No | Slightly | By force | By force |
In all baths, bathe stability and all on 1st, reduce afterwards.Next day, copper hydroxide precipitation occurs.For improving, bathe stability, recommend at least EDDS of 1.1:1: copper ratio.But experiment of the present invention shows oxoethanoic acid: the impact of EDDS mol ratio on the copper deposition quality on substrate.
Test shows that copper deposition quality is along with oxoethanoic acid concentration improves and reduces.When the oxoethanoic acid concentration of electroless copper in bathing is higher, copper-oxoethanoic acid complex compound may form with the competition of Cu-EDDS complex compound and oxoethanoic acid also play complexing agent but not the effect of reductive agent.
Although oxoethanoic acid concentration is enough high, consequently play two kinds of effects (complexing agent and reductive agent), by the reduction process of copper-oxoethanoic acid complex compound, seem to be restricted.Form copper-oxoethanoic acid complex compound and can cause the passivation of bathing unstable and copper plated material.Herein, passivation means copper surface and becomes to electroless copper process non-activity; Electroless copper process stops on passive surface.When the mol ratio of oxoethanoic acid: EDDS is 4.6:1 or 4.6:1 when above, copper deposition quality reduces.Initial reactivity, copper spreadability and passivation are depending on the mol ratio of oxoethanoic acid: EDDS.
Complexing agent plays an important role in electroless copper process.Not each complexing agent all can be used for reduction process.Complexing agent EDDS and copper form the complex compound that can be reduced easily.At the oxoethanoic acid lower than 4.6:1: under EDDS ratio, particularly at 3.6:1 or lower than under 3.6:1, deposition quality (spreadability, backlight) is fabulous.
6. example: use the experiment of thiocarboxylic acid
Containing/not containing the EDTA of thiocarboxylic acid and the comparison of EDDS
In experiment, thioglycolic acid is used as to thiocarboxylic acid.
Use the different test inventories that form of bathing
Service temperature: 55 ℃
Test result
Thioglycolic acid causes the dark color of electroless copper deposition.Sedimentation rate because being used thioglycolic acid to reduce in electroless copper is bathed.
7. example: use the copper deposition sample on glass substrate while bathing containing the copper of different complexing agents: sputter has the glass of Ti/Cu crystal seed
Pre-treatment:
Fig. 4 shows the result of the copper thickness obtaining for different complexing agents.
Claims (15)
1. an electroless copper aqueous solution, it comprises
Cupric ion source,
As the oxoethanoic acid source of reductive agent, and
As at least one poly-amino two succinic acid of complexing agent or the mixture of at least one poly-amino monobutane diacid or at least one poly-amino two succinic acid and at least one poly-amino monobutane diacid,
Wherein the mol ratio of this complexing agent and cupric ion is in the scope of 1.1:1 to 5:1.
2. the electroless copper aqueous solution as claimed in claim 1, wherein the mol ratio of oxoethanoic acid and complexing agent is <4.6:1.
3. as the electroless copper aqueous solution of any one in the claims, wherein the mol ratio of this complexing agent and cupric ion is in the scope of 1.5:1 to 5:1.
4. as the electroless copper aqueous solution of any one in the claims, it contains the thiocarboxylic acid that is less than 0.01ppm.
5. as the electroless copper aqueous solution of any one in the claims, wherein this complexing agent is at least one poly-amino two succinic acid.
6. as the electroless copper aqueous solution of any one in the claims, wherein this complexing agent is quadrol-N, N'-bis-succinic acid (EDDS).
7. as the electroless copper aqueous solution of any one in the claims, wherein this solution further comprises one or more stablizers.
8. the electroless copper aqueous solution as claimed in claim 7, wherein this stablizer is selected from dipyridyl, phenanthroline, sulfydryl-benzothiazole, thiocarbamide or derivatives thereof, prussiate, thiocyanate-, iodide, thanomin, sulfydryl-benzotriazole, Na
2s
2o
3, polymkeric substance, as polyacrylamide, polyacrylate(s), polyethylene glycols or polypropylene glycols or its multipolymer.
9. as the electroless copper aqueous solution of any one in the claims, wherein this solution further comprises hydroxide ion source.
10. as the electroless copper aqueous solution of any one in the claims, wherein this solution is except also comprising the second reductive agent containing oxoethanoic acid.
11. as the electroless copper aqueous solution of claim 10, and wherein this second reductive agent is selected from diphosphanetetroic acid, oxyacetic acid, formic acid and these sour salt.
12. 1 kinds of methods for electroless copper, the method comprises makes substrate contact with the electroless copper aqueous solution as any one in claim 1 to 11.
13. as the method for claim 12, and it is to carry out at the temperature in the scope of 20-60 ℃.
14. 1 kinds as the purposes of the electroless copper aqueous solution of any one in claim 1 to 11, and it is for the plating of printed circuit board (PCB), ic substrate, wafer, mold interconnecting device, indicating meter or plastic paste.
15. 1 kinds as the purposes of the electroless copper aqueous solution of any one in claim 1 to 11, and it is for glass substrate, especially for the plating of the glass substrate of indicating meter.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP11183991 | 2011-10-05 | ||
| EP11183991.6 | 2011-10-05 | ||
| PCT/EP2012/069388 WO2013050332A2 (en) | 2011-10-05 | 2012-10-01 | Formaldehyde-free electroless copper plating solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104040026A true CN104040026A (en) | 2014-09-10 |
| CN104040026B CN104040026B (en) | 2019-01-01 |
Family
ID=46963736
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201280049015.6A Active CN104040026B (en) | 2011-10-05 | 2012-10-01 | Chemical plating copper plating solution without formaldehyde |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US20140242264A1 (en) |
| EP (1) | EP2764135A2 (en) |
| JP (1) | JP6180419B2 (en) |
| KR (1) | KR101953940B1 (en) |
| CN (1) | CN104040026B (en) |
| TW (1) | TWI557271B (en) |
| WO (1) | WO2013050332A2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105624653A (en) * | 2014-11-24 | 2016-06-01 | 罗门哈斯电子材料有限责任公司 | Formaldehyde-free electroless metal plating compositions and methods |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2784181B1 (en) * | 2013-03-27 | 2015-12-09 | ATOTECH Deutschland GmbH | Electroless copper plating solution |
| ES2684353T3 (en) * | 2013-09-25 | 2018-10-02 | Atotech Deutschland Gmbh | Method for depositing a copper sowing layer over a barrier layer and copper plating bath |
| WO2015111291A1 (en) * | 2014-01-27 | 2015-07-30 | 奥野製薬工業株式会社 | Conductive film-forming bath |
| JP6539992B2 (en) * | 2014-11-14 | 2019-07-10 | 凸版印刷株式会社 | Printed circuit board, semiconductor device, method of manufacturing wired circuit board, method of manufacturing semiconductor device |
| EP3035122B1 (en) | 2014-12-16 | 2019-03-20 | ATOTECH Deutschland GmbH | Method for fine line manufacturing |
| EP3035375B1 (en) * | 2014-12-19 | 2017-05-03 | ATOTECH Deutschland GmbH | Treating module of an apparatus for horizontal wet-chemical treatment of large-scale substrates |
| TWI713737B (en) | 2016-05-04 | 2020-12-21 | 德商德國艾托特克公司 | Process for depositing a metal or metal alloy on a surface of a substrate including its activation |
| KR102428755B1 (en) * | 2017-11-24 | 2022-08-02 | 엘지디스플레이 주식회사 | Optical fiber capable of converting wavelength and backlight unit using the same |
| EP3578683B1 (en) | 2018-06-08 | 2021-02-24 | ATOTECH Deutschland GmbH | Electroless copper or copper alloy plating bath and method for plating |
| EP3670698B1 (en) | 2018-12-17 | 2021-08-11 | ATOTECH Deutschland GmbH | Aqueous alkaline pre-treatment solution for use prior to deposition of a palladium activation layer, method and use thereof |
| TWI764121B (en) | 2019-04-04 | 2022-05-11 | 德商德國艾托特克公司 | A method for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization |
| EP3839092A1 (en) | 2019-12-20 | 2021-06-23 | ATOTECH Deutschland GmbH | Method for activating at least one surface, activation composition, and use of the activation composition to activate a surface for electroless plating |
| CA3190848A1 (en) | 2020-08-27 | 2022-03-03 | Andre Beyer | A method for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization |
| CN114507850A (en) * | 2021-12-06 | 2022-05-17 | 华东理工大学 | Chemical formula of environment-friendly plating solution for non-formaldehyde electroless copper plating on ceramic substrate by ink-jet printing |
| CN115679305B (en) * | 2023-01-03 | 2023-03-10 | 湖南源康利科技有限公司 | Chemical copper plating treatment process for surface of aluminum foil for printed board |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4617205A (en) * | 1984-12-21 | 1986-10-14 | Omi International Corporation | Formaldehyde-free autocatalytic electroless copper plating |
| US5741555A (en) * | 1995-05-22 | 1998-04-21 | The Dow Chemical Company | Succinic acid derivative degradable chelants, uses and compositions thereof |
| US5846925A (en) * | 1995-08-30 | 1998-12-08 | The Dow Chemical Company | Succinic acid derivative degradable chelants, uses and compositions thereof |
| US6660071B2 (en) * | 2000-06-19 | 2003-12-09 | Murata Manufacturing Co., Ltd. | Electroless copper plating bath, electroless copper plating method and electronic part |
| CN1867697A (en) * | 2003-10-17 | 2006-11-22 | 株式会社日矿材料 | Electroless copper plating solution and method for electroless copper plating |
| US7220296B1 (en) * | 2005-12-15 | 2007-05-22 | Intel Corporation | Electroless plating baths for high aspect features |
| CN101104929A (en) * | 2006-07-07 | 2008-01-16 | 罗门哈斯电子材料有限公司 | Environmentally friendly electroless copper compositions |
| CN102191491A (en) * | 2010-03-10 | 2011-09-21 | 比亚迪股份有限公司 | Chemical copper-plating solution and chemical copper-plating method |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2761874A (en) | 1954-09-30 | 1956-09-04 | Dow Chemical Co | Amino derivatives of n-alkyl substituted aspartic acids and their functional derivatives |
| US3158635A (en) | 1959-03-18 | 1964-11-24 | Stauffer Chemical Co | Bis-adduction products and methods of preparing same |
| US3632704A (en) * | 1967-12-04 | 1972-01-04 | Stauffer Chemical Co | Method for modifying electrically nonconductive surfaces for electroless plating |
| US4315045A (en) * | 1978-12-19 | 1982-02-09 | Crown City Plating Co. | Conditioning of polyamides for electroless plating |
| JPS57116031A (en) | 1981-01-13 | 1982-07-19 | Tokyo Organ Chem Ind Ltd | N-substituted polyamine and its preparation |
| US4668532A (en) * | 1984-09-04 | 1987-05-26 | Kollmorgen Technologies Corporation | System for selective metallization of electronic interconnection boards |
| GB9422762D0 (en) * | 1994-11-11 | 1995-01-04 | Ass Octel | Use of a compound |
| JPH0949084A (en) * | 1995-05-31 | 1997-02-18 | Nitto Chem Ind Co Ltd | Electroless copper plating bath using diamine type biodegradable chelating agent |
| JPH11513058A (en) * | 1995-08-30 | 1999-11-09 | ザ ダウ ケミカル カンパニー | Succinic acid derivative degradable chelating agent, its use and composition thereof |
| US20020064592A1 (en) | 2000-11-29 | 2002-05-30 | Madhav Datta | Electroless method of seed layer depostion, repair, and fabrication of Cu interconnects |
| KR100529371B1 (en) * | 2003-07-29 | 2005-11-21 | 주식회사 엘지화학 | Catalyst precursor resin composition and preparation method of light-penetrating electro-magnetic interference shielding material using the same |
| EP1696719A4 (en) * | 2003-11-14 | 2008-10-29 | Bridgestone Corp | Electromagnetic-shielding light-transmitting window material and method for producing same |
| US20060251801A1 (en) * | 2005-03-18 | 2006-11-09 | Weidman Timothy W | In-situ silicidation metallization process |
| KR100702797B1 (en) * | 2005-12-09 | 2007-04-03 | 동부일렉트로닉스 주식회사 | Method of fabricating the copper interconnection layer in semiconductor device |
| KR20080083790A (en) | 2007-03-13 | 2008-09-19 | 삼성전자주식회사 | Eletroless copper plating solution, production process of the same and eletroless copper plating method |
-
2012
- 2012-10-01 EP EP12766668.3A patent/EP2764135A2/en not_active Withdrawn
- 2012-10-01 CN CN201280049015.6A patent/CN104040026B/en active Active
- 2012-10-01 US US14/350,153 patent/US20140242264A1/en not_active Abandoned
- 2012-10-01 KR KR1020147008668A patent/KR101953940B1/en active IP Right Grant
- 2012-10-01 WO PCT/EP2012/069388 patent/WO2013050332A2/en active Application Filing
- 2012-10-01 JP JP2014533846A patent/JP6180419B2/en active Active
- 2012-10-05 TW TW101136996A patent/TWI557271B/en active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4617205A (en) * | 1984-12-21 | 1986-10-14 | Omi International Corporation | Formaldehyde-free autocatalytic electroless copper plating |
| US5741555A (en) * | 1995-05-22 | 1998-04-21 | The Dow Chemical Company | Succinic acid derivative degradable chelants, uses and compositions thereof |
| US5846925A (en) * | 1995-08-30 | 1998-12-08 | The Dow Chemical Company | Succinic acid derivative degradable chelants, uses and compositions thereof |
| US6660071B2 (en) * | 2000-06-19 | 2003-12-09 | Murata Manufacturing Co., Ltd. | Electroless copper plating bath, electroless copper plating method and electronic part |
| CN1867697A (en) * | 2003-10-17 | 2006-11-22 | 株式会社日矿材料 | Electroless copper plating solution and method for electroless copper plating |
| US7220296B1 (en) * | 2005-12-15 | 2007-05-22 | Intel Corporation | Electroless plating baths for high aspect features |
| CN101104929A (en) * | 2006-07-07 | 2008-01-16 | 罗门哈斯电子材料有限公司 | Environmentally friendly electroless copper compositions |
| CN102191491A (en) * | 2010-03-10 | 2011-09-21 | 比亚迪股份有限公司 | Chemical copper-plating solution and chemical copper-plating method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105624653A (en) * | 2014-11-24 | 2016-06-01 | 罗门哈斯电子材料有限责任公司 | Formaldehyde-free electroless metal plating compositions and methods |
| CN105624653B (en) * | 2014-11-24 | 2019-03-15 | 罗门哈斯电子材料有限责任公司 | Formaldehydeless electrodeless metal plating coating composition and method |
| TWI655319B (en) * | 2014-11-24 | 2019-04-01 | 羅門哈斯電子材料有限公司 | Formaldehyde-free electroless metal plating compositions and methods |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6180419B2 (en) | 2017-08-16 |
| JP2014528517A (en) | 2014-10-27 |
| WO2013050332A3 (en) | 2014-03-13 |
| WO2013050332A8 (en) | 2013-07-11 |
| TW201323654A (en) | 2013-06-16 |
| KR20140090145A (en) | 2014-07-16 |
| CN104040026B (en) | 2019-01-01 |
| WO2013050332A2 (en) | 2013-04-11 |
| US20140242264A1 (en) | 2014-08-28 |
| TWI557271B (en) | 2016-11-11 |
| KR101953940B1 (en) | 2019-03-04 |
| EP2764135A2 (en) | 2014-08-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104040026A (en) | Formaldehyde-free electroless copper plating solution | |
| CA1255975A (en) | Formaldehyde-free autocatalytic electroless copper plating | |
| KR102142173B1 (en) | Electroless copper plating solution | |
| CN107002241B (en) | The bath compositions of chemical plating for metal and metal alloy | |
| US5803957A (en) | Electroless gold plating bath | |
| EP3023515A2 (en) | Formaldehyde-free electroless metal plating compositions and methods | |
| CN101899688A (en) | Cyanide-free gold plating solution for plating gold | |
| JP2016516902A (en) | Electroless copper plating solution | |
| KR20040050887A (en) | Electroless Gold Plating Solution | |
| KR101821852B1 (en) | Alkaline plating bath for electroless deposition of cobalt alloys | |
| JP3800213B2 (en) | Electroless nickel plating solution | |
| CN101634021A (en) | Electroless gold plating solution | |
| US11396706B2 (en) | Electroless copper or copper alloy plating bath and method for plating | |
| KR20090069231A (en) | Electroless gold plating bath for copper substrate and gold plating using the same | |
| US11512394B2 (en) | Electroless gold plating bath | |
| JP2000345359A (en) | Electroless gold plating solution | |
| JPH0243373A (en) | Electroless gold plating liquid | |
| JPS61153281A (en) | Chemical copper plating solution |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |