Abstract: When relatively hard Au bump electrodes are mass-produced by electrolytic plating while ensuring usually required properties such as a non-glossy property and shape-flatness, combination of conditions, such as low liquid temperature, high current density, and low concentration of added Tl (thallium) that is an adjuvant, will be selected by itself. However, in such conditions, there is a problem that it is difficult to maintain the Tl concentration in a plating solution and, when the Tl concentration is reduced, defective appearance of the Au bump electrodes is generated by anomalous deposition. Conventionally, there has been no means to directly monitor minute Tl concentration and the Tl concentration has been controlled by analyzing the plating solution periodically. However, this can not prevent generation of a lot of defective products.

Abstract: To provide a hard gold-based plating solution which enables selective partial plating treatment and is suitable for electronic components such as a connector. A hard gold-based plating solution of the present invention comprises: a soluble gold salt or a gold complex; a conductive salt; and a chelating agent, wherein the hard gold-based plating solution further comprises an aromatic compound having one or more nitro groups, for example, an aromatic compound selected from the group consisting of nitrobenzoic acid, dinitrobenzoic acid and nitrobenzene sulfonic acid. The hard gold-based plating solution further comprises at least one metal salt of a cobalt salt, a nickel salt and a silver salt, or polyethyleneimine as an organic additive.

Abstract: The invention relates to an electrolyte used in connection with the deposition of a gold-tin alloy on an electroplatable substrate. This solution generally includes water; stannous and/or stannic tin ions, a complexing agent to render the stannous and/or stannic tin ions soluble, complexed gold ions, and an alloy stabilizing agent that includes ethoxylated compounds with phosphate ester functional group, brightening additives based on ethoxylated phosphate esters and alkali metal fatty acids dipropionates. The brighteners may be used alone or in conjunction with each other to achieve beneficial synergistic effect. The alloy stabilizing agent is present in an amount sufficient to stabilize the composition of the gold-tin deposit over a usable current density range. The solution has a pH of between 2 and 10 and the gold ions and tin ions are present in relative amounts sufficient to provide a deposit having a gold content less than 90% by weight and a tin content greater than 10% by weight.

Abstract: A metal plating bath containing alcohol compounds that inhibit or retard the consumption of plating bath additives. The additives are chemical compounds that improve the brightness of the plated metal, the physical properties of the plated metal especially with respect to ductility and the micro-throwing power as well as the macro-throwing power of the plating bath. The alcohol compounds that inhibit or retard the consumption of additives increases the life of the plating bath and improves the efficiency of the plating process. The plating baths containing the alcohol compounds that inhibit or retard additive consumption can be employed to plate copper, gold, silver, palladium, platinum, cobalt, cadmium, chromium, bismuth, indium, rhodium, ruthenium, and iridium.

Abstract: A method for forming a quaternary alloy film of Co—W—P—Au for use as a diffusion barrier layer on a copper interconnect in a semiconductor structure and devices formed incorporating such film are disclosed. In the method, a substrate that has copper conductive regions on top is first pre-treated by two separate pre-treatment steps. In the first step, the substrate is immersed in a H2SO4 rinsing solution and next in a solution containing palladium ions for a length of time sufficient for the ions to deposit on the surface of the copper conductive regions. The substrate is then immersed in a solution that contains at least 15 gr/l sodium citrate or EDTA for removing excess palladium ions from the surface of the copper conductive regions.

Abstract: A relatively stable, weakly acidic, non-cyanide electroplating solution for deposition of Au—Sn alloys over a range of compositions. The solution consists of Au and Sn chloride salts, as well as ammonium citrate as a buffering agent and sodium sulphite and L-ascorbic acid as stabilizers. Preliminary electroplating experiments with the developed solution indicate that uniform, homogeneous deposits can be achieved over a range of compositions, including the technologically important eutectic and near euctectic values.

Abstract: Disclosed are cyanide free electroplating solutions for gold or alloys thereof; said solutions comprising gold in the form of a soluble sulfite complex, an added source of sulfite and/or bisulfite ion and a supporting electrolyte; and said solutions further comprising both an organic polyamine or mixture of polyamines of molecular weight from about 60 to 50,000, and an aromatic organic nitro compound; wherein the pH of said solutions is below about 6.5.

Abstract: A solution for electroplating gold-copper-silver alloys. The solution comprises gold, copper and silver, each in the form of a cyanide complex. The solution further comprises a divalent sulfur compound capable of brightening and leveling the electroplated deposit of the gold-copper-silver alloy. Optionally, a source of cyanide ions such as a free alkali cyanide, is included in the solution. In addition, additives such as surface active agents, buffers and/or conductivity salts may also be included to impart a particular feature or characteristic to the solution. The invention additionally comprises a process for electroplating up to about 20 microns of a gold-copper-silver alloy upon a substrate utilizing these novel solutions. The alloy is deposited upon a substrate which is immersed in the solution, by electroplating at a current density of between about 1 and 15 ASF, a pH of between about 8-11 at a temperature of between about 100.degree.-170.degree. F.