Patent Number: 7,045,389

Title: Method for fabricating a semiconductor devices provided with low melting point metal bumps

Abstract: A semiconductor device (1) comprising electrodes formed on a semiconductor chip (2) and bumps (3) which consist of a low melting point metal ball spherically formed and having a given size and which are adhesive bonded to the electrodes (5). The electrodes (5) are formed from an electrode material of Cu or a Cu alloy, Al or an Al alloy, or Au or a Au alloy. When the electrode material is composed of Al or an Al alloy, the electrodes contain, on the electrode material layer of Al or an Al alloy, at least one layer (6) composed of a metal or metal alloy (preferably a metal selected form Ti, W, Ni, Cr, Au, Pd, Cu, Pt, Ag, Sn or Pb, or an alloy of these metals) having a melting point higher than the electrode material. The low melting point metal balls (3) are adhesive bonded to the electrodes (5) preferably with a flux. The low melting point metal balls (3) adhesive bonded to the respective electrodes (3) may also be reflowed to form semispherical bumps (10) before use.

Inventors: Tatsumi; Kohei (Kawasaki, JP), Shimokawa; Kenji (Kawasaki, JP), Hashino; Eiji (Kawasaki, JP)

Assignee: Nippon Steel Corporation

International Classification: H01L 21/48 (20060101); B23K 31/00 (20060101); H01L 23/48 (20060101); H01R 43/00 (20060101)

Expiration Date: 5/16/02018