An aqueous acid bath for the galvanic deposition of bright, ductile and smooth copper coats which is suitable for decorative purposes as well as for strengthening the conductors of printed circuits. The bath is characterized by a content of polyalkylene glycol ether. When combined with thio compounds containing water-soluble groups, these additions produce an electrolyte with excellent stability. Polymeric phenazonium compounds, polymeric nitrogen compounds and/or thio compounds containing nitrogen may also be successfully combined, in addition, depending on the desired properties.

Disclosed are methods for repairing seed layers prior to subsequent metallization during the manufacture of electronic devices.

A process for electroplating metal on a resistive substrate and the article of manufacture produced therefrom are disclosed. The metal layer is electroplated onto the resistive substrate in an electroplating bath having a polarization parameter .xi. less than approximately 10 such that the metal layer is of substantially uniform thickness. The polarization parameter .xi. of less than approximately 10 for the electroplating bath can be achieved by numerous means, such as by providing a low metal ion concentration in the electroplating bath or by adding one or more additives to the electroplating bath. The present invention may be used with a variety of metals and resistive substrates.

A copper-plating electrolyte includes an aqueous copper salt solution, a water-soluble .beta.-naphtholethoxylate compound having the formula ##STR1## wherein n is an integer from 10 to 24, one selected from the group consisting of a disulfide having the formula XO.sub.3 S(CH.sub.2).sub.3 SS(CH.sub.2).sub.3 SOX.sub.3 and a water-soluble mercaptopropanesulfonic acid or salt thereof having the formula HS(CH.sub.2).sub.3 SO.sub.3 X, where X is sodium, potassium, or hydrogen, a water-soluble polyethylene glycol having a molecular weight ranging from about 4,600 to about 10,000, and a water-soluble polyvinylpyrrolidone having a molecular weight ranging from about 10,000 to about 1,300,000.

Disclosed is an improved electrolyte formulation for the electrodeposition of copper onto electronic devices substrates and a process using the formulation. The formulation is a solution which contains copper alkanesulfonate salts and free alkanesulfonic acids and which is intended for the metallization of micron or sub-micron dimensioned trenches or vias.