KR20070017949A - Chromium-free antitarnish adhesion promoting treatment composition - Google Patents

Abstract

The present invention is a zinc ion; Metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions and combinations thereof; And any electrolyte that does not contain potassium or sodium ions, and which is substantially free of chromium, wherein the treatment composition relates to adhesion of a polymer to a material on a substrate or on a material. To form a film that improves.

Antirust, Adhesive, Aqueous Treatment Composition, Electrolyte, Substrate, Coating

Description

Chromium-free antitarnish adhesion promoting treatment composition

The present invention relates to a rust-preventive adhesion promoting treatment composition, and more particularly to a rust-preventive adhesion promoting treatment composition that is substantially free of chromium.

The rust resistance of metals and the strong adhesion between the metals and polymers can be used in various applications such as printed circuits, electronic packages, trims of vehicle bodies (for example, aluminum to PVC or ABS plastic), steel belt tires and paint or other polymeric coatings. It has long been requested in the field of application. For example, the rust resistance of Cu films for application to printed circuits is required for shelf life and to withstand exposure to heat during lamination and soldering in printed circuit processes. In addition, the antirust coating prevents oxidation of Cu and prevents reaction with the polymer substrate while being exposed to moisture and temperature during the service life of the part. This function is important for maintaining good bonding between Cu and the polymer. In electronic package applications, good adhesion is required for the electrical connector between the metal jack and the molded plastic insulating sheath surrounding it. As a second example, the inner lead of the metal lead frame may be encapsulated in a polymer molding resin in the assembly of the electrical package to accommodate the integrated circuit.

The adhesion between the polymer resin and the metal substrate is improved by covering the metal substrate with a second metal that bonds more strongly to the polymer resin. Suitable coatings include, for example, non-reactive oxide forming metals such as nickel and nickel alloys, or intermetallic forming coatings such as, for example, tin on copper substrates. Such coatings as well as other coatings are known in US Pat. No. 4,888,449 (Crane et al.), Which is incorporated herein by reference in its entirety.

Recently, coatings containing zinc / chromium (ZnCr) have been widely used in copper foils and lead frames in electronic applications, improving the bond strength of metals to rust resistant polymer substrates. Such coatings are typically electrodeposited in alkaline solutions containing NaOH, Zn and Cr (VI) ions to form a mixture of Zn / Cr oxides that provide rust resistance.

US Patent No. 4,387,006 describes a method of surface treatment of copper foils used in printed wire boards. The copper foil is electrolyzed in an aqueous solution of zinc chromate containing zinc ions and chromium (VI) ions and immersed in an aqueous solution containing aminosilane, sodium silicate and / or potassium silicate.

U. S. Patent No. 5,230, 932, U. S. Patent No. 5,098, 796, and U. S. Patent No. 5,022, 968 describe techniques and compositions for improving the rust and oxidation resistance of copper and copper-based alloy materials. Electrolytic coating is performed by immersing the material in an aqueous electrolyte containing NaOH, zinc ions and chromium (VI) ions. The coating exhibits rust resistance at 190 ° C. or higher.

U.S. Patent No. 5,250,363 (Chen) describes techniques for improving the rust and oxidation resistance of metal substrates. The substrate is immersed in an aqueous solution containing NaOH, zinc ions and chromium (VI) ions, and the chromium-zinc coating is electrolytically coated on the substrate. The coating exhibits rust resistance at 230 ° C. or higher and can be easily removed by immersion in sulfuric acid.

It is also desired that under certain conditions some of these coatings can reduce moisture osmosis between the lead frame and the molding formulation. This effect is believed to be caused by the formation of water vapor from the moisture trapped and accumulated under the die attach paddle when the device is applied at a soldering temperature (eg, a temperature of about 230 ° C.). effect) "can be reduced. The generation of such water vapor is believed to be responsible for the failure of the device due to cracking and stack separation. In addition, due to growing environmental issues and stricter disciplines in the industry, alternative solder temperatures tend to be even higher, with metal and polymer adhesive properties increasingly becoming more and more away from solders containing lead and other toxic elements. It will be more important.

Many compositions are known that provide adhesion between a metal and a polymer substrate. US Pat. No. 5,573,845 to Parthasarathi et al. Describes a synthetic material having a metal core, preferably surface treated. A needle-shaped (nodular) coating layer having an apparent thickness of less than 275 mm 3 is adjacent to at least one portion of the metal core. The coating coating layer can be removed from the metal core without any noticeable change to the metal core surface treatment.

US Pat. No. 5,449,951 to Parthasarathi et al. Describes a lead frame with improved adhesion to polymer resins. The lead frame is covered with a thin layer containing chromium, zinc or a mixture of chromium and zinc. The coated lead frame shows improved adhesion to the polymer resin.

Korean Patent Publication No. 00/74131 A1 (Lee et al.) Describes a method of assembling a semiconductor device package, in which a device / lead frame assembly is formed, and then an adhesive enhancement coating is applied to the device / lead frame assembly. After deposition on the exposed surface, the capsule is coated. The coating is a metal coating which may be an inorganic Zn / Cr coating. Said publication is in particular incorporated herein by reference in its entirety.

US Patent No. 5,252,855 (Ogawa) describes the formation of aggregates of acicular catalysts by anodizing the substrate to improve the adhesion between the copper-based metal substrate and the polymer resin. U.S. Patent No. 4,939,316 to Mahulikar et al. Discloses improving polymer bond strength by anodizing aluminum alloy substrates. Other satisfactory coatings include antioxidant materials having a thickness of 300 to 5,000 mm 3 as described in US Pat. No. 5,192,995 (Yamazaki et al.).

As is known in the art, sodium (Na) and / or potassium (K) ions are frequently used in immersion baths. However, sodium and potassium ions have the disadvantage that these ions can potentially diffuse into the silicon die and cause defects in the device being fabricated. Such defects are well reported [see, for example, "metal cladding", which defines chloride and sodium contamination from molding formulations, die coatings and die attach coatings on April 12, 2000. [Microelectronic Defects Database, CALCE Electronic Products and Systems Center, University of Maryland; And “The Effect of Ionic Impurities in Die Attach Adhesive in Performing Devices”, which defines die attach adhesive as a specific source of ionic contamination. See Barnes and Robinson, Proceedings of 34th Electronics Components Conf., May, 1984, p. . 68)].

In addition, the presence of chromium (VI) ions in the plating solution causes environmental problems in handling and disposal. Although plating baths containing chromium (VI) have been used around the world for decades, the use of Cr (VI) has increased due to increased concerns about health and environmental impacts. Therefore, it would be desirable to replace the Cr (VI) plating bath with a less toxic Cr (III) bath or to completely remove Cr.

Accordingly, there is a need in the art to provide an aqueous treatment composition that promotes adhesion and rust resistance, utilizing any electrolyte substantially free of chromium (VI) and free of potassium and sodium ions.

The gist of the invention

In one embodiment, the present invention provides a zinc ion; Metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions and combinations thereof; And an electrolyte that does not contain potassium or sodium ions, and which is substantially free of chromium, wherein the treatment composition can form a coating on the material, the coating on the material. Improves the adhesion of the polymer to

In another embodiment, the present invention provides a zinc or zinc oxide atom; Rustproof and substantially free of chromium, including metals or metal oxides selected from the group consisting of tungsten, molybdenum, cobalt, nickel, zirconium, titanium, manganese, vanadium, iron, tin, indium, silver and combinations thereof A material coated with an adhesion promoting aqueous treatment composition, wherein the coating exhibits rust resistance for at least 30 minutes at 250 ° C., and the coating contains a nodular structure that enhances the adhesion of the polymer to the material.

In another aspect, the invention provides zinc ions; Metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions and combinations thereof; And contacting the material with an antirust adhesion promoting aqueous treatment composition comprising any electrolyte free of potassium or sodium ions and substantially free of chromium; And passing a current through the treatment composition under conditions which deposit a rustproof adhesion promoting coating on the material to form a material coated with the rustproof adhesion promoting coating (the coating enhances the adhesion of the polymer to the material). It relates to a method of forming a material coated with an antirust adhesion coating, comprising the step.

These and other aspects will be described in more detail later in the detailed description of the invention.

The invention will be more fully understood from the following detailed description with reference to the accompanying drawings.

1 (a), 1 (b), and 1 (c) show scanning electron micrographs (SEM) of surfaces treated according to the compositions and methods of the present invention after 2, 5 and 10 seconds of plating time, respectively. )to be.

2 is a bar graph showing the effect of treatment on the bond strength between various surface treatments and molding blends and treated surfaces.

Surprisingly, the present invention has found that anti-rust adhesion promoting aqueous treatment compositions can be prepared that form strong bonds between metals and polymers and exhibit environmental and health effects with respect to handling and disposal of the compositions. According to the present invention, the present invention now has improved bond adhesion between the polymeric material and the metal and is substantially free of chromium (VI), thus preventing the environmental and health problems in handling the solution. Adhesion Promoting Aqueous Treatment Compositions were Found.

As pointed out above, the present invention provides a composition comprising (1) zinc ions; (2) metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions and combinations thereof ; And (3) any electrolyte that does not contain potassium or sodium ions, and which is substantially free of chromium, wherein the anti-rust adhesion promoting aqueous treatment composition is characterized by the adhesion of a polymer to a material or a substrate. An improving film is formed on the material or on the substrate. Each of these compositions is described in more detail below.

The zinc ion component of the treatment composition of the present invention may be derived from any zinc salt that forms a sufficient amount of zinc ions in an aqueous solution. Examples of useful zinc salts include, but are not limited to, zinc sulfate, zinc oxide, zinc chloride, zinc fluoride, zinc acetate, and combinations thereof. It is also understood that the hydrates of the zinc salts can also be used alone or in combination in the compositions of the present invention. In a preferred embodiment, for example, the zinc salt is zinc sulfate heptahydrate (ZnSO ₄ 7H ₂ O).

Preferably zinc ions are present in the compositions of the present invention based on the total volume of the composition from about 0.1 g / L to about 100 g / L, more preferably from about 0.5 g / L to about 50 g / L, most preferably about 0.5 g / L to about 20 g / L. In one preferred embodiment the zinc salt is zinc sulfate heptahydrate (ZnSO ₄ .7H ₂ O) and is present in the composition at about 2 g / L to about 80 g / L.

The antirust adhesion promoting aqueous treatment composition of the present invention further comprises metal ions that can form co-deposits with zinc and form the ultimate nodule structure deposited on the surface of the material or substrate. Useful metal ions include tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions and silver ions. Metal ions can be used alone or in combination in the treatment compositions of the present invention.

Metal ions can be derived from the corresponding metal salt or hydrate or metal acid thereof. Examples of metal salts or metal salt hydrates useful in the compositions of the present invention include nickel sulfate or nickel sulfate hydrate, ammonium molybdate, molybdenum oxide, potassium permanganate, manganese sulfate, and combinations thereof. Examples of metal acids include molybdate, tungstic acid, tungstosilicic acid and combinations thereof. In a preferred embodiment, the metal ions are molybdenum ions, tungsten ions or combinations thereof. The present invention is not limited to these examples, and other metal salts, hydrates thereof, or metal acids may be used.

Preferably the metal ions are present in the composition of the present invention at about 5 to about 20,000 ppm, more preferably at about 15 to about 2,000 ppm, most preferably at about 25 to about 300 ppm, based on the total portion of the composition.

In many instances, zinc salts provide sufficient conductivity to the compositions of the present invention to allow for the deposition of zinc and metal ions on the material or substrate. However, when the concentration of zinc salt is low, there may not be sufficient electrical conductivity for proper electrolytic deposition of the composition. In such cases, it is desirable to add additional electrolyte to the treatment composition so that a suitable deposition can be achieved. Any water soluble salt may be used as the electrolyte, but the electrolyte preferably contains no sodium or potassium. As described in WO 00/74131, the presence of sodium or potassium ions in an aqueous plating composition teaches that WO 00/74131 teaches that these ions are dispersed into silicon dies and subsequently It will cause bad defects. Therefore, electrolytes containing no sodium or potassium are preferred.

Examples of useful electrolytes including, but not limited to, ammonium sulfate, boric acid, citric acid, gluconic acid, rubidium hydroxide, ammonium chloride and combinations thereof. Generally, the electrolyte component comprises about 1 g / L to about 500 g / L, more preferably about 5 g / L to about 200 g / L, most preferably about 10 g / L to about 50 g / L.

As noted above, substantially no chromium is present in the antirust adhesion promoting aqueous treatment composition of the present invention. The presence of chromium results in unavoidable contamination from chemical sources or the environment. As defined herein, “substantially free of chromium” generally means that the concentration of chromium is less than about 0.001% by weight, based on the total weight of the composition. Chromium (VI) has been known to be toxic and does not benefit the environment, health and safety. Thus, the compositions of the present invention that are substantially free of chromium do not fall under this disadvantage.

The treating composition of the present invention may be prepared by mixing a suitable amount of zinc and metal compounds and optionally an electrolyte in water to obtain each component at the desired concentration. The pH of the solution is added by adding an acid (e.g. boric acid, sulfuric acid, hydrochloric acid, citric acid, gluconic acid, etc.) or a base that does not contain sodium or potassium (e.g., calcium hydroxide, magnesium hydroxide, rubidium hydroxide, ammonium hydroxide, etc.). Is set. Preferred pH of the treatment composition according to the present invention is about 0.5 to about 14.0, more preferred pH range is about 1.5 to about 13.5, most preferred pH range is about 2.5 to about 13.0. In addition, when the pH of the composition according to the invention is in the neutral range (eg, pH 5-9), a co-formulation, such as a salt of citric acid or gluconic acid, may be necessary to keep the metal ions in the soluble state in the plating solution. .

In general, the rust free adhesion promoting aqueous treatment composition according to the present invention may be provided in a known process for applying a coating. For example, prior to coating the material or substrate, the material or substrate may be electrolytically degreased in a commercial alkaline cleaner or NaOH to remove any residual lubricant, oil, dust or surface oxides. An example of the concentration of the cleaner is typically 30 g / l for 20 seconds at a bath temperature of 130 ° F. and a current density of 30 asf (ampere per square foot (A / ft ² ). However, any desired wash parameters can be used as known in the art. After washing, the sample is immersed in 5% sulfuric acid solution to activate the surface.

The following conditions are preferable during deposition. The temperature of the plating bath during deposition may preferably range from about 100 to about 150 ° F., more preferably from about 110 to about 140 ° F., and most preferably from about 120 to about 140 ° F. The current density during deposition may range from about 2 to about 200 asf, more preferably from about 5 to about 100 asf, most preferably from about 5 to about 30 asf. Deposition time may preferably range from about 1 to about 200 seconds, more preferably from about 2 to about 50 seconds, most preferably from about 2 to about 20 seconds.

Once deposited on a material or substrate, the composition of the present invention forms a coating containing the nodular structure as shown in FIGS. 1 (a), 1 (b) and 1 (c). The thickness of the coating is preferably in the range of about 15 to about 500 mm 3, depending on the deposition conditions (described in more detail below). On average preferably about 25 to about 1,000 nodular structures per 16 μm ² , and most preferably the average density of the nodule structures is about 50 to about 500 per μm ² . The average length of each constituent structure is preferably from about 0.01 μm to about 1 μm, more preferably from about 0.05 μm to about 0.5 μm. Preferred aspect ratios (length to diameter) are about 1: 1 to about 8: 1 and more preferably about 2: 1 to about 6: 1.

Most nodular structures do not extend vertically from the surface, but are believed to extend from the surface at various angles, forming meshes that intersect each other. The polymer flowing on the gaps between the individual nodular structures follows the curved path between the gaps and, as it solidifies, the polymer appears to be mechanically locked in place. In addition, the coating layer improves the adhesion of the material or substrate to the polymer. The presence of the nodule structure on the substrate surface improves the mechanical locking of the polymer adhesive compared to the surface without the nodule structure. For example, after exposure of the sample at 85% RH / 80 to 85 ° C. for 168 hours and subsequent thermal shock at about 260 ° C. soldering for 120 seconds, preferably in the range exceeding 1,000 psi, moreover, depending on the type of polymer adhesive Preferably bond strengths of 1,100 to 2,400 psi can be obtained. The coating layer is firmly bonded to the metal substrate and does not separate in the coating layer itself as is typical at the contact surface between the metal substrate and the coating layer or in the copper oxide coating. In the absence of a nodular antirust coating as described herein, the bond strength between the metal and the polymer is typically less than half the strength described above.

The coating layer contributes to preventing oxidation at temperatures where the composite material may be exposed during storage, processing or use. These temperatures typically reach about 250 ° C. Although the coating layer has discrete gaps and gaps, no extension occurs completely through the coating layer or the oxidation site. In addition to anti-oxidation, the coating layer provides corrosion protection properties that dilute the chloride, sulfide and other contaminant concentrations found in industrial environments or on the operator's fingers.

The rust-preventing adhesion promoting coatings and methods of application thereof described herein can be applied at any process step to any conductor based on electrochemical principles. For example, copper and copper alloys, as well as nickel, iron, aluminum, steel, stainless steel, zinc, tin, silver, palladium, gold, titanium, carbon, and any other material with sufficient conductivity to pass electrical current or The substrate may be electroplated. In addition, metallized nonconductors can also be electroplated themselves. In another example, it is convenient to apply the anti-corrosive coating of the present invention after silver plating in a lead frame fabrication process. If desired, the coatings of the present invention may be removed at locations where wire bonding is needed using masks in subsequent silver stripping processes typically used to remove back plating or spill-over plating of silver. Alternatively, the antirust coating of the present invention may be applied after IC chip attachment and wire bonding. This approach does not require removing the coating at the wire bonding area.

The invention is described in more detail by the following examples. All parts and percentages are by weight and all temperatures are in degrees Celsius unless specifically stated otherwise.

Example  One

C110 copper foil (> 99.9% Cu and <0.05% O) was electrolytically degreased in commercial alkaline cleaners to remove residual lubricants, contaminants and oxides from the surface. The washed copper foil was immersed in a solution containing 10 g / L of ZnSO ₄ 7H ₂ O, 10 g / L of (NH ₄ ) ₂ SO ₄ and 25 ppm of W (tungsten as tungsten silicic acid). A plating electric current 10A / ft ² (ASF) in the region of 0.035ft ² was applied to the 2, 5 and 10 seconds. The sample was then washed and dried. 1 (a), 1 (b) and 1 (c) show scan electron micrographs (SEM) of the treated surfaces at three time intervals. In each case, nodular form is seen.

Copper foil samples were subjected to a tape test using Scotch 600 tape. The tape was first pressed onto the plated surface and then peeled off from the surface. The adhesive remains visible on the plated sample, indicating that nodular structures are deposited on the copper foil.

The sample was further baked at 250 ° C. for 30 minutes. The sample showed no oxidation even after baking, while the untreated portion was severely oxidized. These results indicate that the deposited coating provides good rust resistance. The baked sample is further subjected to a tape test using the Scotch 600 tape described above. The adhesive remains visible on the plated sample, which in turn indicates the presence of nodular structures deposited on the copper foil.

Example  2

A C110 copper foil sample with pure copper dendritic crystals on one side and exposed on the other side was immersed in 5% by weight of H ₂ SO ₄ for 30 seconds to remove any surface oxides present. The sample is placed in a device exposing only one side to an aqueous plating composition containing ZnSO ₄ 7H ₂ O 10 g / L, (NH ₄ ) ₂ SO ₄ 20 g / L and W 25 ppm, and the plating current 10ASF is set to 0.104 ft ² . Was applied for 5 seconds. The sample was then washed and dried. The same procedure was repeated on the second sample exposing the opposite surface to the same solution and plating current. Samples were further subjected to a 95 ° C./55% RH test for 60 minutes to promote long term shelf life in hot and humid conditions. The sample is then baked at 190 ° C. for 30 minutes and shows no oxidation. The untreated portion was heavily oxidized. These results indicate that the coating provides good rust resistance.

Example  3

The C110 copper foil was electrolytically degreased in a commercial alkaline cleaner to remove residual lubricants, contaminants and oxides from the surface. 5 ns of plating current 5ASF in a region of 0.035 ft ² for 5 seconds ZnSO ₄ .7H ₂ O 5g / L, NiSO ₄ .6H ₂ O 3g / L and MITIQUE (Inorganic acid composition containing 1 to 3% ammonium molybdate; Hubbard Hall , Waterbury, CT) was applied in a solution containing 2.5 ml / l. The samples were then washed and dried and subjected to a tape test using Scotch 600 tape. The tape was first pressed onto the plated surface and then peeled off from the surface. The adhesive remains visible on the plated sample. These results indicate that nodular structures are deposited.

The sample was further subjected to a baking test at 250 ° C. for 10 minutes. The sample shows no oxidation at all after baking. The untreated portion was heavily oxidized. These results indicate that the coating provides good rust resistance.

Example  4

A 0.03 inch thick C7025 copper foil (Cu 96.2%, Ni 3.0%, Si 0.65%, and Mg 0.15%) was electrolytically degreased in commercial alkaline cleaners to remove residual lubricants, contaminants and oxides from the surface. Plating current 10ASF was applied in a solution containing 10 g / L ZnSO ₄ 7H ₂ O and 1.5 ml / l MITIQUE in the region of 0.035 ft ² for 10 seconds. The sample was then washed and dried. Tape test using a Scotch 600 tape indicates that the adhesive is transferred to the treated surface and a nodular or roughened surface is obtained. Additional samples were plated, capsule coated using a Sumicon 6300 molding compound and then subjected to 85% RH / 85 ° C. moisture test for 168 hours as described in test standard IPC / JEDEC J-STD-020A. Applied. After exposing the sample to the solder for 120 seconds at about 260 ° C., the adhesive strength is measured in the tensile strength test, with the capsule coated metal sample removed from the molding formulation and the separation force recorded using an Instron tensile tester. No loss of bond strength is found when the sample is compared to a sample that is not exposed to temperature / humidity. In contrast, a sample without nodule treatment typically loses at least 50% of its original bond strength.

Example  5

The C110 copper foil was electrolytically degreased in a commercial alkaline cleaner to remove residual lubricants, contaminants and oxides from the surface. Plating current 10ASF was applied in a solution containing 10 g / L ZnSO ₄ 7H ₂ O and 45 ppm MoO _{3 in} the region of 0.035 ft ² for 10 seconds. The samples were then washed and dried and subjected to a tape test using Scotch 600 tape. The tape was first pressed onto the plated surface and then removed from the surface. The adhesive remains visible on the plated sample. These results indicate that nodular structures are deposited.

The sample was further subjected to a baking test at 250 ° C. for 10 minutes. The sample shows no oxidation at all after baking. The untreated portion was heavily oxidized. These results indicate that the coating provides good rust resistance.

Example  6

A 0.03 inch thick C7025 copper foil was electrolytically degreased in a commercial alkaline cleaner to remove residual lubricants, contaminants and oxides from the surface. Plating current 10ASF was applied in a solution containing 10 g / L ZnSO ₄ 7H ₂ O and 30 ppm Mo (as molybdate) in the region of 0.035 ft ² for 10 seconds. The samples were then washed and dried and subjected to a tape test using Scotch 600 tape. The tape test indicates that the adhesive is delivered to the treated surface and a nodular or roughened surface is obtained. Additional samples were plated, capsule coated using Sumicon 6300 and Shintsu KMC-289-3ECS molding formulations, and then 85 hours for 168 hours as described in test standard IPC / JEDEC J-STD-020A. Applied to the% RH / 85 ° C. moisture test. The sample was exposed to the solder for 120 seconds at about 260 ° C. and then the adhesive strength was measured. As shown in Fig. 2, the bond strength is hardly found to be lost when compared to an unexposed sample.

Example  7

A 0.03 inch thick C7025 copper foil was electrolytically degreased in a commercial alkaline cleaner to remove residual lubricants, contaminants and oxides from the surface. Plating current 10ASF was applied in a solution containing ZnSO ₄ 7H ₂ O 15 g / L, (NH ₄ ) ₂ SO ₄ 15 g / L and 25 ppm W (as tungsten silicic acid) in the region of 0.035 ft ² for 5 seconds. The samples were then washed and dried and subjected to a tape test using Scotch 600 tape. The tape was first pressed onto the plated surface and then peeled off from the surface. The adhesive remains visible on the plated sample. These results indicate that nodular structures are deposited.

The sample was further subjected to a baking test at 250 ° C. for 10 minutes. The sample shows no oxidation at all after baking. The untreated portion was heavily oxidized. These results indicate that the coating provides good rust resistance.

Additional samples were plated, capsule coated using Sumicon 6300 and Shinto KMC-289-3ECS molding formulations, and then 168 hours as described in test standard IPC / JEDEC J-STD-020A. During 85% RH / 85 ° C. moisture test. The sample was exposed to the solder for 120 seconds at about 260 ° C. and then the adhesive strength was measured. As shown in Figure 2, no bond strength was found to be lost when compared to an unexposed sample.

Example  8

A 0.03 inch thick C7025 copper foil was electrolytically degreased in a commercial alkaline cleaner to remove residual lubricants, contaminants and oxides from the surface. Plating current 5ASF was applied in a solution containing 12.5 g / L NaOH, 2.25 g / L zinc and 0.65 g / L W for 4 seconds in the region of 0.035 ft ² . The samples were then washed and dried and subjected to a tape test using Scotch 600 tape. The tape was first pressed onto the plated surface and then peeled off from the surface. The adhesive remains visible on the plated sample. These results indicate that nodular structures are deposited.

The sample was further subjected to a baking test at 250 ° C. for 30 minutes. The sample shows no oxidation at all after baking. The untreated portion was heavily oxidized. These results indicate that the coating provides good rust resistance.

Claims (43)

Zinc ions, Metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions and combinations thereof; and Includes any electrolyte that does not contain potassium or sodium ions, An antirust adhesion promoting aqueous treatment composition substantially free of chromium and capable of forming a coating on the material, the coating improving the adhesion of the polymer to the material. The antirust adhesion promoting aqueous treatment composition according to claim 1, wherein the zinc ions are derived from zinc salts. The antirust adhesion promoting aqueous treatment composition according to claim 2, wherein the zinc salt is selected from the group consisting of zinc sulfate, zinc oxide, zinc chloride, zinc fluoride, zinc acetate, hydrates thereof, and combinations thereof. The antirust adhesion promoting aqueous treatment composition according to claim 1, wherein the zinc ion comprises about 0.1 g / L to about 100 g / L. The antirust adhesion promoting aqueous treatment composition according to claim 1, wherein the zinc ion comprises about 0.5 g / L to about 50 g / L. The anti-rust adhesion promoting aqueous treatment composition according to claim 1, wherein the zinc ion comprises about 0.5 g / L to about 20 g / L. The antirust adhesion promoting aqueous treatment composition according to claim 1, wherein the metal ion is derived from a corresponding metal salt or metal acid. The antirust adhesion promoting aqueous treatment composition according to claim 7, wherein the metal salt is selected from the group consisting of nickel sulfate, ammonium molybdate, molybdenum oxide, potassium permanganate, manganese sulfate, hydrates thereof, and combinations thereof. The antirust adhesion promoting aqueous treatment composition according to claim 7, wherein the metal acid is selected from the group consisting of molybdic acid, tungstic acid, tungsten silicic acid. The antirust adhesion promoting aqueous treatment composition according to claim 1, wherein the metal ion is selected from the group consisting of molybdenum and tungsten. The anti-rust adhesion promoting aqueous treatment composition of claim 1, wherein the metal ions comprise from about 5 to about 20,000 ppm based on the total portion of the treatment composition. The anti-rust adhesion promoting aqueous treatment composition of claim 1 wherein the metal ions comprise from about 15 ppm to about 2,000 ppm based on the total portion of the treatment composition. The anti-rust adhesion promoting aqueous treatment composition according to claim 1, wherein the metal ions comprise from about 25 ppm to about 300 ppm based on the total portion of the treatment composition. The antirust adhesion promoting aqueous treatment composition according to claim 1, wherein the optional electrolyte is selected from the group consisting of ammonium sulfate, boric acid, citric acid, gluconic acid, rubidium hydroxide, ammonium chloride and combinations thereof. The anti-rust adhesion promoting aqueous treatment composition according to claim 1, wherein the electrolyte comprises about 1 g / L to about 500 g / L. The anti-rust adhesion promoting aqueous treatment composition according to claim 1, wherein the electrolyte comprises about 5 g / L to about 200 g / L. The anti-rust adhesion promoting aqueous treatment composition according to claim 1, wherein the electrolyte comprises about 10 g / L to about 50 g / L. Zinc or zinc oxide atoms and A metal or metal oxide atom selected from the group consisting of tungsten, molybdenum, cobalt, nickel, zirconium, titanium, manganese, vanadium, iron, tin, indium, silver and combinations thereof, A material coated with an anticorrosive adhesive treatment coating that is substantially free of chromium and contains a nodular structure that provides rust resistance for at least 30 minutes at 250 ° C. and improves the adhesion of the polymer to the material. 19. The method of claim 18, wherein the material is from the group consisting of copper, copper alloys, nickel, iron, aluminum, steel, stainless steel, zinc, tin, silver, palladium, gold, titanium, carbon, metallized nonconductors, and combinations thereof. A material coated with a rust preventive adhesive coating comprising a material of choice. 19. The material coated with an antirust adhesive coating according to claim 18, wherein the thickness of the coating on the substrate is in the range of about 15 to about 500 mm 3. The material coated with a rust preventive adhesive coating of claim 18, wherein the coating contains from about 25 to about 1,000 nodular structures per 16 μm ² . 19. The method of claim 18, wherein the average length of the nodule structures range from about 0.01 μm to about 1 μm, respectively, and the aspect ratio (length to diameter) is from about 1: 1 to about 8: 1, coated with an antirust adhesive coating. matter. 19. The material coated with an antirust adhesive coating according to claim 18, comprising a coated substrate. A substrate according to claim 23 comprising an electronic device. A substrate according to claim 23 comprising a device / lead frame assembly. The rust-resistant substrate of claim 18, wherein the coated substrate has improved adhesion greater than 1,000 psi after exposure to 168 hours at 85% RH / 80 to 85 ° C. and subsequent heat shock for 120 seconds at about 260 ° C. soldering. Material coated with an adhesive treatment coating. Zinc ions; Metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions and combinations thereof; And contacting the material with an antirust adhesion promoting aqueous treatment composition comprising any electrolyte free of potassium or sodium ions and substantially free of chromium; and Passing an electrical current through the treatment composition under conditions such that the antirust adhesion promoting coating is deposited on the material to form a material coated with the antirust adhesion promoting coating (the coating enhances the adhesion of the polymer to the material). A method for forming a material coated with an antirust adhesion promoting coating comprising a. The method of claim 27 wherein the material is from the group consisting of copper, copper alloys, nickel, iron, aluminum, steel, stainless steel, zinc, tin, silver, palladium, gold, titanium, carbon, metallized nonconductors, and combinations thereof A method of forming a material coated with an antirust adhesion promoting coating comprising a material of choice. The method of claim 27, wherein the conditions include a temperature in the range of about 100 to about 150 ° F. 29. The method of claim 27, wherein the current is in the range of about 2 to about 200 asf. The method of claim 27, wherein the conditions comprise a deposition time in the range of about 1 to about 200 seconds. 28. The antirust coating according to claim 27, wherein the zinc ion is derived from a zinc salt selected from the group consisting of zinc sulfate, zinc oxide, zinc chloride, zinc fluoride, zinc acetate, hydrates thereof and combinations thereof. A method of forming a coated material. The method of claim 27, wherein the zinc ion comprises about 0.1 g / L to about 100 g / L. The metal salt of claim 27 wherein the metal ion is selected from the group consisting of nickel sulfate, ammonium molybdate, molybdenum oxide, potassium permanganate, manganese sulfate, hydrates thereof and combinations thereof; Or a material coated with an antirust adhesion promoting coating derived from a metal acid selected from the group consisting of molybdic acid, tungstic acid, tungsten silicic acid and combinations thereof. The method of claim 27, wherein the metal ions comprise from about 5 to about 20,000 ppm based on the total portion of the treatment composition. The method of claim 27, wherein the electrolyte is selected from the group consisting of ammonium sulfate, boric acid, citric acid, gluconic acid, rubidium hydroxide, ammonium chloride, and combinations thereof. The method of claim 36, wherein the electrolyte comprises from about 1 g / L to about 500 g / L. The method of claim 27, wherein the coating on the substrate has a thickness in the range of about 15 to about 500 GPa. The method of claim 27, wherein the coated substrate contains from about 25 to about 1,000 nodular structures per 16 μm ² . 28. The method of claim 27, wherein the average length of the nodule structures range from about 0.01 μm to about 1 μm, respectively, and the aspect ratio (length to diameter) is from about 1: 1 to about 8: 1, coated with an antirust adhesion promoting coating. How to form a substance. The method of claim 27, wherein the material comprises a substrate. 42. The method of claim 41, wherein the substrate comprises an electronic device. 42. The method of claim 41, wherein the substrate comprises a device / lead frame assembly.

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