REPRODUCTION METHOD OF BUMP

PROBLEM TO BE SOLVED: To provide a reproduction method of a bump. SOLUTION: A defective bump is removed from a wafer through chemical etching. During etching, etchant damages a passivation layer on a wafer somewhat. Therefore, a global metal layer covering a bonding pad and a passivation layer is necessary, before forming a new under ball metallurgy(UBM) layer. After a defective bump is removed, a damaged passivation layer is covered by forming an auxiliary passivation layer. Then, a new UBM layer and a new bump are formed. In another method, a defective bump and a UBM layer are removed by chemical etching, without forming a metal layer. Alternatively, an auxiliary passivation layer is formed, and a damaged passivation layer is covered. Lastly, a new UBM layer and a new bum are formed. It is possible to reproduce a defective bump and to improve yield of bump manufacturing through chemical etching.