Showing papers on "Electroless nickel plating published in 1998"

Method of forming electric pad of semiconductor device and method of forming solder bump

Abstract: Electroless nickel plating and gold plating is performed on an aluminum electrode in order to construct a highly reliable electrode. The steps are: depositing zinc on the aluminum electrode with zincate treatment liquid containing sodium hydroxide and zinc oxide; immersing it in solution which is prepared by dissolving sodium hypophosphite as a reducing agent into de-ionized water, followed by addition of de-ionized water while adjusting for the pH of 9.0 to 12.0 with sodium hydroxide solution, so as to make a total volume of 1000 ml; nickel-plating the aluminum electrode of the semiconductor device by using electroless nickel plating solution of oxidation-reduction reacting type containing sulfur compound as a reaction promoter, under a condition of the pH at 4.0 to 6.8 and a temperature of 80 to 90° C.; electroless gold-plating by substitutional reaction type; and, electroless gold-plating by oxidation-reduction reacting type, so as to form a nickel film containing phosphor and gold plated films on all aluminum electrodes of the semiconductor device. In this way, a nickel plate film of good electrical conductivity and also a gold plate of a thick film on all aluminum electrodes of the semiconductor device are formed, without resulting in corrosion of the passivation film and the aluminum electrodes.

Synthesis and Corrosion Behavior of Electroless Ni–P– Si3N4 Composite Coatings

Abstract: The ability to codeposit ®ne particulate matter with an electroless nickel matrix is a major step in the development of processes aimed at the engineering of surfaces. The prime objective of incorporating the particulate matter is to improve wear and corrosion resistance. The most frequently studied systems are electroless Ni±P±SiC, Ni±P±Al2O3, Ni±P±diamond, Ni±P±PTFE and Ni±P±Cr3C2. Very little information is available on electroless Ni±P±Si3N4 composite coatings. Since Si3N4 has high hardness, good oxidation resistance and good chemical stability, it is worthwhile to study this combination. In the present study we codeposit Si3N4 with electroless nickel on medium carbon steel and evaluate its hardness and corrosion resistance. A proprietary high phosphorus electroless nickel plating bath was used. The pH of the bath was 4.8. Medium carbon steel coupons of 30 mm diameter and 5 mm thickness were surface ground (Ra ˆ 0:4 im) and suspended in the plating bath. The plating bath was maintained at a constant temperature of 88 1 8C. The coupons were plated for 2 h. For the preparation of composite coatings, the Si3N4 powder (size ,10 im) of a calculated quantity was mixed thoroughly with 10 ml of the plating solution using a mortar and pestle and then transferred to the plating bath. This process ensures the distribution of Si3N4 paticles throughout the bath. To obtain a uniform dispersion of Si3N4 particles in suspended form in the bath, the plating solution was stirred using a magnetic stirrer. The electroless plated samples were heat treated for 1 h at temperatures of 200, 300, 400, 500 and 600 8C to determine the change in hardness upon heating to different temperatures. In order to represent common industrial practice no special atmosphere was maintained during heat treatment. Hardness measurements were carried out using a Leitz Micro Vickers Tester employing a load of 0.1 kg. Five readings were taken on each deposit and the values were then averaged. Potentiodynamic polarization studies were carried out using EG&G PAR (Model 362) scanning potentiostat. The electrolyte used was non-deaerated 3.5% NaCl solution. The specimens were masked with lacquer so that only a 1 cm area was exposed to the electrolyte. A saturated calomel electrode (SCE) was used as a reference electrode. The corrosion potential (Ecorr) and corrosion current (icorr) were obtained from the polarization curves using the Tafel extrapolation method. Both the Ni±P and Ni±P±Si3N4 coatings did not exhibit any porosity when subjected to the ferroxyl test. Both of them were found to be adherent when tested by the bent test method, following ASTM B 571 and the thermal shock method. The thickness of the deposit was in the range of 22±25 im in all cases after 2 h of deposition. Fig. 1 shows that cross-section of the electroless Ni±P±Si3N4 deposits when viewed by optical microscopy. The incorporation of the Si3N4 particles in the deposit is clearly visible. Fig. 2 shows the weight percentage of Si3N4 particles in the electroless nickel deposit as a function of its concentration (g=l) in the plating bath. It can be deduced from the ®gure that the percentage incorporation of Si3N4 particles (the percentage of Si3N4 represents only the weight percent of Si3N4 throughout this communication unless otherwise stated) increases with an increase in concentration and reaches a maximum at a concentration of 10 g=l. Beyond this concentration of 10 g=l, a slight decrease in the percentage incorporation is observed. A decrease in the percentage of incorporation of the second phase particles was observed earlier in the electroless Ni±P±Al2O3 system by Rajagopal [1]. The increase in percentage incorporation of Si3N4 particles in the electroless Ni±P matrix with increase in its concentration in the plating bath can be

Method of forming electroless metal plating layers on one single surface of a plastic substrate and the product thereof

Abstract: Disclosed is a method of forming electroless metal plating layers on one single surface of a plastic substrate and the product thereof. The method includes steps of degreasing or pre-etching the material for forming the substrate, etching the material, adding catalysis, activating, drying, spraying non-conducting paint on a first surface of the material, accelerating, forming an electroless copper plating layer on a second surface of the material, activating, forming an electroless nickel plating layer on the second surface of the material, sealing, dehydrating, drying, inspecting, and packing. Wherein, the steps of spraying non-conducting paint and drying give the material a beautiful painted appearance on the first surface thereof. The non-conducting paint on the first surface of the material facilitates easy formation of smooth electroless copper and nickel plating layers on the second surface of the material. Therefore, a product of the method can be used in electronic products requiring high sensitivity.

Direct electroless nickel plating on copper circuits using DMAB as a second reducing agent

Abstract: Generally, palladium catalyst treatment is applied to initiate the electroless Ni-P plating on the copper patterns because copper does not have a catalytic action for the oxidation of hypophosphite. However, when electroless nickel films are deposited on circuit boards with high density copper patterns by this process, many extraneous deposits are observed after electroless nickel plating. If electroless nickel plating is progressed on the copper patterns without palladium catalyst treatment, extraneous nickel depositions are inhibited. Direct electroless nickel plating of the copper patterns by the addition of dimethyl amine borane (DMAB) as a second reducing agent into the plating bath is investigated.

The effects of immersion zincation to the electroless nickel under-bump materials in microelectronics packaging

Abstract: One of the methods used for flip chip mounting is by solder bumping that utilizes Ni/Au under-bump metallurgy. Electroless nickel plating has been preferred over conventional electroplating due to its simplicity, good control, and reproducibility. Experiments are carried out to determine the optimum aluminum surface conditions for nickel adhesion, through studies of surface morphology and transformation during pretreatment. Zincation baths are used to condition the aluminum surfaces for nickel plating. The effects of the period and the number of times of the zincation process on the mechanical strength of the electroless nickel deposits are investigated. From SEM and AFM characterization, transitions of zinc grain size and surface roughness are observed. Grains are large with distinct grain boundaries for immersion time of 5 s, but decrease in size and lose their characteristic shapes as the zincation time increases. A double zincation produces a more compact deposit with smaller size grains compared to single zincation. Length of immersion time during the second zincation also affects the physical properties such as shear strength after 1 hr of electroless nickel plating on the 80 /spl mu/m/spl times/80 /spl mu/m Al bond-pads of a commercial bare microchip. The elemental composition transitions of the zinc deposits formed by different zincation times and bath compositions are also investigated using SEM-EDX and XPS.

Method for forming electrode of semiconductor element

Abstract: PROBLEM TO BE SOLVED: To provide electroless nickel plating and gold plating methods on an aluminum electrode for forming a highly reliable electrode. SOLUTION: Zinc is deposited 14 on the aluminum electrode 12 with zincate treating liquid containing sodium hydroxide and zinc oxide. Then, sodium hypophosphite being a reducing agent is dissolved in pure water. Pure water is added while it is adjusted to pH 9.0-12.0 with sodium hydroxide solution and it is immersed into solution 15 which is set to be 1000 mL in total. Then, nickel plating is executed with the condition of pH 4.0-6.8 at 80-90°C by using oxidation-reduction reaction electroless nickel plating liquid containing sulfur compound with the aluminum electrode 12 of the semiconductor element as reaction accelerator. Thus, a nickel film 16 containing phosphorus and gold plating films 17 and 18 are obtained in all the aluminum electrodes 12 of the semiconductor element by executing substitution reaction electroless gold plating and oxidation reduction-type electroless plating. COPYRIGHT: (C)1999,JPO

Method and apparatus for treating electroless nickel plating waste solution

Abstract: PROBLEM TO BE SOLVED: To effectively treat components in a plating waste soln. to recover nickel or phosphoric acid by treating the plating waste soln. with a chelating resin and subsequently oxidizing and decomposing hypophosphorous acid, phosphorous acid and an org. acid. SOLUTION: A packed column V is packed with a chelating resin and a plating waste soln. is injected into the column under pressure by a pump P-1 to be passed from below to above to be brought into contact with the chelating resin. Subsequently, silver plating is applied to the inner peripheral wall of an oxidizing treatment tank T-4 and surface roughening treatment is applied to the surface of the silver layer. By this method, the surface of the silver layer becomes silver peroxide by ozone used for oxidizing treatment and oxidation is further accelerated by the catalytic action of the silver peroxide. By this constitution, an org. acid is decomposed into water and carbon dioxide in the presence of the oxidizing agent by the irradiation with ultraviolet rays within the oxidizing treatment tank T-4 housing the waste soln. after the adsorptive removal of nickel while hypophosphorous acid and phosphorous acid become phosphoric acid by oxidation. The waste soln. after treatment is supplied to a reaction tank T-5 having a stirrer M to be reacted with a precipitant such as calcium hydroxide or the like under stirring and mixing. COPYRIGHT: (C)1999,JPO

Gold wire bondability of electroless gold plating using disulfiteaurate complex

Abstract: Generally, contact or terminal areas are coated with nickel as a barrier layer; subsequently, gold plating is performed to maintain reliability of electrical interconnection. Treatment using dilute solutions of palladium ions have been applied to initiate electroless nickel plating on copper substrates because copper has no catalytic action for the oxidation of hypophosphite. However, trace amounts of palladium ions may remain on the unwanted areas and extraneous nickel deposits are often observed. We confirmed that nickel films without extraneous deposits can be formed using the activation solutions containing dimethyl amine borane (DMAB). Bondability on the electrolessly deposited gold was greatly influenced by the phosphorus contents of the deposited nickel films as the underlayer. Bonding strength after electroless gold plating was increased with increasing phosphorus contents in the nickel films. Stabilizers in the electroless gold plating also influenced the bonding strength. Baths containing cupferron or potassium nickel cyanide as a stabilizer showed superior bondability. Gold deposits having strong orientation with Au(220) and Au(311) indicated high bond strength.

Method of preparing hard disc including treatment with amine-containing zincate solution

Abstract: A method of preparing a hard disc comprising steps of: immersing an aluminum or aluminum alloy substrate in a zincate solution containing a zinc compound, an alkali hydroxide, and at least one amine to thereby form a zincate film on the surface of the substrate, immersing the zincate film-formed substrate in an electroless nickel plating solution comprising a water-soluble nickel salt, a complexing agent, and a hypophosphite to thereby form a nickel--phosphorus alloy layer on the surface of the zincate film-coated substrate, and forming a magnetic layer on the nickel--phosphorus alloy layer.

Application of Solvent Extraction to Treatment of Electroless Nickel Plating Wastewater.

Abstract: Electroless plating is widely used in electronics, semiconductor and automobile industries as a surface treatment technique, because uniform thickness metal can be deposited on plastics, ceramics or polymers with intricately shaped surfaces. Above all, electroless nickel plating using hypophosphite as a reducing agent is very popular and has been studied a lot, since it gives excellent plated metal surfaces with corrosion resistance, lubricity and magnetic properties. As metal deposition progresses in this process, however, phosphorous acid increases in the plating bath, which causes degradation of the bath solution. Therefore, the bath itself must be disposed after a certain number of turnovers before the degradation occurs. The waste solution from electroless nickel plating bath contains a large quantity of nickel, hypophosphite, phosphite and organic compounds such as citrate, malate or succinate. It is quite harmful to the environment and at the same time, these hazardous wastes can be viewed as resources if properly handled. Therefore, it is very important to develop an effective extraction technique removing these chemical substances separately.In the present study, the application of solvent extraction to the treatment of electroless nickel plating waste water was investigated. In the treatment of caustic alkaline plating waste water, TOMAC is favorable to the extraction of nickel and citrate, and the separation from hypophosphite and phosphite. It is difficult to apply TOMAC to the treatment of ammoniacal alkaline plating waste water, while the use of chelating extractants such as LIX 26 is favorable to extraction of nickel. Meanwhile, the application of solvent extraction to the treatment of acidic plating waste water is difficult.

Fabrication of Nickel Dots Using Selective Electroless Deposition on Silicon Wafer

Abstract: The selective deposition of nickel on n-Si(100) wafer in aqueous solution was investigated. It was confirmed by cross-sectional FE-TEM examination that the deposition of nickel occurred from a solution of nickel ions prepared by excluding the hypophosphite reducing agent from the conventional electroless nickel plating bath, and that this deposition reaction accompanied the formation of SiO2. This finding shows that the electrons needed to reduce the nickel ions to the metal are supplied directly from the Si wafer. By utilizing this galvanic displacement reaction, nickel metal in the form of minute dots measuring 1 μm in diameter was selectively deposited using a silicon oxide layer as the resist in combination with a two-step process, which consisted of the first step of immersing a Si wafer into a solution containing nickel ions but no reducing agent to form nuclei of nickel metal, and the second step of immersing the wafer with the nuclei into a conventional electroless nickel plating bath to cause the...

Method of pretreatment for electroless nickel plating

Abstract: A method for preventing formation of a "bridge" is provided for electrolessly plated nickel or gold between copper patterns. A circuit board having a copper pattern is immersed in a pretreatment solution containing thiosulfate for electroless nickel plating, or the pretreatment solution is sprayed over the board. The pretreatment solution may be incorporated with an additive, such as a pH adjustor, complexing agent, surfactant or corrosion inhibitor.

Tem investigation of initiation of electroless nickel deposition on pure iron

Abstract: SummaryIn this paper, the nucleation and the growth of electroless nickel plating on pure iron were investigated by TEM. The results show that the initiation is inhomogeneous and its structure is crystalline and coherent with the substrate to some degree. From the composition depth distribution measured by AES, the initial crystalline structure is determined by its composition (phosphorus content) and there exists a process of dissolution of Fe substrate followed by codeposition of the dissolved Fe2+ ions with Ni, P during initiation.

Board and manufacture thereof

Abstract: PROBLEM TO BE SOLVED: To improve a conductive pattern in adhesion to a glass board, by a method wherein the surface of the glass board is previously subjected to a pre-treatment where catalyst nuclei are applied to the surface of the glass board or the like, and a nickel layer, a layer whose main component is palladium, and a conductive layer are laminated thereon. SOLUTION: Sn adsorbed to the surface of a glass board 1 is substituted by Pd, the surface of the glass board 1 is subjected to a pre-treatment where catalyst nuclei are applied, and then the glass board 1 is dipped into an electroless nickel plating solution so as to be plated with a nickel plating layer 2. Then, a palladium layer 3 is formed thereon using an electroless palladium plating solution which contains a reducing agent that does not generate hydrogen as a side reaction product at deposition of palladium. In succession, a protective resist 4 is formed on the palladium layer 3, a part of the palladium layer 3 where the protective resist 4 is not provided is subjected to etching for the formation of a conductor pattern, the protective resist 4 is removed, and then a conductive layer 5 is formed on the conductor pattern.

Method for plating to hard disk substrate

Abstract: PROBLEM TO BE SOLVED: To form electroless nickel plating films which are free from defects, such as pits, and have a good adhesion property on hard disk substrates made of glass and ceramics. SOLUTION: In the electroless nickel plating of hard disk substrates made of the glass or the ceramics, the substrates are treated with a catalyst liquid consisting essentially of a water-soluble palladium salt and an amine-base complexing agent and not containing a tin salt after the substrate is subjected to surface adjusting treatment and are then subjected to washing and drying and thereafter, the substrates are immersed into an electroless nickel plating liquid and are subjected to electroless nickel plating.

Glass coated semiconductor device and its manufacture

Abstract: PROBLEM TO BE SOLVED: To form an electrode by electroless nickel plating uniformly, precisely and with a good contact in a wafer in a mesa semiconductor device coated with glass. SOLUTION: A p type semiconductor region 2 is formed in one major surface of a semiconductor substrate having an n type semiconductor region 1 with a high density of impurities and an n type semiconductor region 3 with a high density of impurities is formed on the other major surface. A mesa groove is provided in a specified region in one of the major surfaces so that a pn junction may be exposed. A glass coating 5 and a glass reduced film 51 not containing metal of glass components are formed in the mesa part in sequence. An anode electrode 20 is provided on the p semiconductor region 2 and a cathode electrode 30 is provided on the n semiconductor region 3 with ohmic contact respectively. Electroless nickel plating can be made uniformly and with a good contact on the surface of the semiconductor regions 2 and 3 respectively for forming electrodes. No nickel plating is made on the glass coating 5 since the glass reduced film 51 exists.

Formation of bump electrode of semiconductor device

Abstract: PROBLEM TO BE SOLVED: To enable easy formation of a bump electrode only on an aluminum electrode requiring the bump electrode in a semiconductor device and also to enable suppression of deterioration of a plating solution. SOLUTION: A native oxide film 2 on a surface of an aluminum electrode 1 is removed. Thereafter, in order to prevent re-formation of a native oxide film, a semiconductor device 3 is immersed into an alkaline solution containing Ni, a laser beam 9 is emitted on the aluminum electrode 1 requiring a bump electrode to locally heat only the vicinity of the electrode and to form an Ni particle film 5. The device is washed with pure water, immersed into an electroless nickel plating solution, the laser beam 9 is emitted on the aluminum electrode 1 requiring a bump electrode, and then an Ni film 6 is formed by an electroless nickel plating process. The device is washed with pure water. Thereafter the device is immersed into an electroless Au-plating solution, the laser beam 9 is emitted on the Al electrode 1 requiring the bump electrode, and then an Au film 7 is formed by the electroless plating process. Local heating by irradiation with the laser beam 9 enables a plating reaction to advance only on the Al electrode 1 requiring the bump electrode, whereby the bump electrode can be formed and also deterioration of the plating solution can be suppressed.

Electrode-forming method of glass-coated semiconductor device

Abstract: PROBLEM TO BE SOLVED: To form a nickel electrode which is uniform and superior in adhesion by dipping a semiconductor wafer in hydrofluoric acid or dilute hydrofluoric acid, making the semiconductor surface having no lead based glass coating film to be exposed, and performing first non-electrolytic nickel plating, after the wafer has been dipped in nitric acid and further in dilute nitric acid SOLUTION: After a lead based glass coating film 5 is formed in a mesa part, silicon oxide films 6 on the surfaces of a P -type semiconductor region 2 of an anode layer and an N -type semiconductor region 3 of a cathode layer are dipped in dilute hydrofluoric acid and eliminated Lead fluoride 11, generated in the above process, is dipped in nitric acid and further in dilute nitric acid and is eliminated by cleaning, using hot water and ultrasonic wave After drying, heat treatment is performed in a hydrogen atmosphere at a specific temperature, thereby eliminating lead ions By electroless nickel plating, an anode electrode 20 and a cathode electrode 30 are formed Hence electrodes can be formed uniformly and densely in a wafer, wherein the electrodes make ohmic contact with a semiconductor region with good adhesion

Pretreatment of electroless nickel plating

Abstract: PROBLEM TO BE SOLVED: To obtain a plating film having excellent adhesion property without influencing the dimensional accuracy of parts by subjecting a metal plate to be treated by electroless nickel plating to electrolysis pretreatment using it a cathode in an electrolytic cell. SOLUTION: A metal part such as a stainless steel plate having poor adhesion property of nickel plating is used as a cathode and electrolyzed in an electrolytic cell to activate the metal surface. Then the metal part is subjected to electroless nickel plating. Or, the metal part is subjected to PR electrolysis and then to cathode electrolysis for the equivalent time to activate the metal surface. The concn. of the iron metal salt used for the electrolytic soln. is preferably adjusted to 0.02 to 0.2 mol. concn. range which does not cause precipitation of the metal on the cathode. The acid used for the electrolytic soln. consists of one or more kinds of inorg. acids or org. acids. A metal corrosion preventing agent, a metal ion sealing agent, a dispersant and a surfactant may be added to the electrolytic soln. A minute amt. of metal precipitated by the cathode electrolysis improves the adhesion property of the electroless nickel plating film in the succeeding process. COPYRIGHT: (C)1999,JPO

High frequency induction heating coil, semiconductor manufacture device, and manufacture of high frequency induction heating coil

Abstract: PROBLEM TO BE SOLVED: To prevent the evaporation of phosphorus (P) which is an impurity from nickel plating applied for corrosion resistance on the surface of a induction heating coil so that phosphorus does not enter an epitaxial layer during growing in an epitaxial growth device for heating a susceptor by using an induction heating coil SOLUTION: Electroless nickel plating is applied to the surface of a high frequency induction heating coil 11, and baked at 350-420 degC in vacuum or under normal pressure for one hour or more Prior to assembling the induction heating coil 11 in an epitaxial growth device, phosphorus in the electroless nickel plating is crystallized, and non-crystallized excess phosphorus is separated The high frequency induction coil 11 obtained is used as a heater for heating a susceptor 3 of the epitaxial growth device

Nickel hypophosphite solutions containing increased nickel concentration

Abstract: This invention relates to aqueous solutions containing Ni cation and hypophosphite anion which have a Ni cation concentration greater than 36 grams/liter. Such solutions have utility in electroless nickel plating baths and processes as make-up solutions and replenishing solutions. The increased concentration of Ni cation results from the addition of the nickel salt of an alkyl sulfonic acid to the solution.

Treatment of waste liquid of electroless nickel plating

Abstract: PROBLEM TO BE SOLVED: To provide a waste liq. treating method simple in treating method, good in removing efficiency especially of phosphorus, capable of efficient treatment with a relatively small-scale equipment and capable of reducing phosphorus, COD, BOD, etc., to a concn. as low as a general industrial waste water which can be treated as a mixed waste water, in a concentrated plating waste liq. of an electroless nickel plating. SOLUTION: In the treating method of the plating waste liq., a sulfuric acid having 50-80% concn., preferably 75% concn., is added to the plating waste liq. and agitated to convert the waste liq. to a highly acidic state of pH0.5-1.5, preferably pH0.5-0.8, then a lime soln. such as slaked lime having 30-50% concn. is added to the waste liq. and agitated to convert the waste liq. to pH10-12 and a phosphorus in the plating waste liq. is removed as a precipitate of calcium phosphate. A nickel precipitation accelerating agent such as palladium may be added previously to the plating waste liq. forcedly precipitate metallic nickel by self decomposition and to convert hypophosphorous acid into phosphorus acid easy to react with calcium.

Nickel plating method and semiconductor device

Abstract: PROBLEM TO BE SOLVED: To provide a nickel plating method capable of forming a nickel plating film good in solder wettability in a relatively short time. SOLUTION: On an alminum pad 12 formed on a silicon wafer 10, a primary nickel plating film 14a having >=5 wt.% P content is formed by using an electroless nickel plating soln. of a medium phosphorus type or a high phosphorus type to secure its barrier properties. After that, a secondary nickel plating film 14b having <5 wt.% P content is formed by using an electroless nickel plating soln. of a low phosphorus type to secure its solder wettability.

Electroless nickel plating liquid and electroless nickel plating method

Abstract: PROBLEM TO BE SOLVED: To obtain an electroless nickel plating method which imparts a smooth Ni-P film to an Al substrate for hard disks by immersing the substrate into a plating liquid which contains nickel ions, their complexing agents and hypophosphorous acid ions and is added with water-soluble sulfur based additives and water-soluble molybdate and/or tungstate in combination. SOLUTION: The sulfur based additives are one or >=2 kinds selected from thiosulfate (sodium thiosulfate, potassium thiosulfate, etc.), thiocyanate (sodium thiocyanate, potassium thiocyanate, etc.), thiourea and thioacetate. The example of the supply source of the nickel ions includes a water-soluble nickel salt, such as nickel sulfate. One or >=2 kinds of monocarboxylic acid, dicarboxylic acid, tricarboxylic acid and carboxylic acids are used in combination as the complexing agents of the nickel ions. The hypophosphorous acid ions are supplied by sodium hypophosphite, etc. The plating liquid is adequately used for the Al substrate for the hard disks by immersing the substrate into the plating liquid after a zinc substitution treatment.

Electronic control device board for car and its formation

Abstract: PROBLEM TO BE SOLVED: To provide a circuit board of low cost, high reliability and high quality to composite junction by applying uniform and extremely thin gold plating to a surface of a board. SOLUTION: In a resin base circuit board 1, an electroless nickel plating layer 4 whose minimum thickness is 2 μm is applied on a conductor pattern 3 constituted of copper by plating bath whose phosphorus concentration is controlled at 5 to 10 wt.% as foundation plating. An electroless gold plating layer 5 which is controlled 0.02 to 0.06 μm thick is applied to a surface layer on the layer 4. COPYRIGHT: (C)2000,JPO

Electroless nickel plating method

Abstract: PROBLEM TO BE SOLVED: To provide an electroless nickel plating method that is a electroless nickel plating method of forming a resist film on the surface of an org. substrate having conductor circuits on the surface on the side having these conductor circuits, then immersing the substrate into an electroless nickel plating liquid to form nickel plating films, and that can avoid the formation of the parts not forming nickel plating films. SOLUTION: In this method for forming nickel plating films on the surfaces of the conductor circuits 11, the conductor circuits 11 are immersed into the first electroless nickel plating liquid 35 to form the first nickel plating film 30 on the surfaces of the conductor circuits 11 and thereafter, the conductor circuits are immersed into the second electroless nickel plating liquid 36 of the deposition rate of nickel higher than that of the first electroless nickel plating liquid 35, by which the second nickel plating films 31 are formed on the surfaces of the first nickel plating films 30.

Low Temperature Electroless Nickel Plating by Use of Ultrasonic Wave

Abstract: The purpose of the study was to lower plating temperature of conventional nickel electroless plating process by use of ultrasonic wave. Effect of bath contents and plating parameters on plating rate was emphasized. Properties of the deposits such as morpology, microstructure, phosphorus content and bardness were studies. Compared with conventional electroless nickel plating process, the deposits obtained are greatly improved with higher phosphorus content, hardness, more compact and uniform microstructure.

Guide roll apparatus and coating apparatus

Abstract: PROBLEM TO BE SOLVED: To provide a guide roll apparatus capable of guiding a nonmagnetic support with good running properties even if a coating film to be formed is thin or the running speed of the coating film is increased. SOLUTION: As for a guide roll (or contact roll) 11, a composite plating film 11b wherein polytetrafluoroethylene fine particles are uniformly dispersed and coprecipitated in an electroless nickel plating film is formed on the surface of a roll 11a constituted of a conductive material such as aluminum or steel. The content of polytetrafluoroethylene thereof is about 30-40 vol.% and the surface roughness thereof is about 0.5-1.0 μm and the wet angle to water on the surface of the coating is set to about 60-80°. COPYRIGHT: (C)2000,JPO

Metallic member for electronic component

Abstract: PROBLEM TO BE SOLVED: To provide an electronic component of which a metallic member with an electroless nickel plating film formed thereon which enables forming an electroless gold plating film having corrosion resistance and a specified thickness is formed on the surface of a metal base. SOLUTION: A metallic member for an electronic component comprises a metal base 10, on which an electroless nickel plating film 20 containing phosphorus is formed. In the electronic component, the electroless nickel film plating film 20 comprises two electroless nickel plating layers 22 and 24, which are different in phosphorus contents. Of the two electroless nickel plating layers 22 and 24, the lower electroless nickel plating layer 22 has higher phosphorus content than that of the upper electroless nickel plating layer 24. COPYRIGHT: (C)1999,JPO