NON-CYANIDE GOLD ELECTROPLATING BATH FOR GOLD BUMP FORMATION AND METHOD FOR FORMING GOLD BUMP

PROBLEM TO BE SOLVED: To provide a non-cyanide gold electroplating bath for gold bump formation having bump hardness and a bump shape suitable for electrode joining with a substrate electrode, and a method for forming a gold pump using the gold plating bath.SOLUTION: The non-cyanide gold electroplating bath for gold bump formation comprises: an alkali salt of gold sulfite or ammonium gold sulfite; a conducting salt; a crystal stabilizer; a crystal conditioner; a buffer; and a brightening agent. The content of the alkali salt of gold sulfite or ammonium gold sulfite is 1 to 20 g/L as a gold concentration, a conductive salt is sodium sulfite, its content is 5 to 150 g/L, and the content of the brightening agent is 0.5 to 100 mmol/L. As the brightening agent, one or more kinds of compounds selected from a sulfoxide and/or sulfone are preferably used.