Method of flux-free contacting of components on a substrate, having the following process steps: producing elevated contact metal bumps of a flux-treated gold-tin solder material on tags of the component; removing flux residues on the surface of the component; melting the elevated contact metal bumps and contacting the contact metal bumps with tags of the substrate.
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.
A semiconductor device comprises a semiconductor element having electrodes and metal bumps are attached to the electrodes. The metal bumps include copper cores and gold surface layers covering the cores. In addition, the metal bumps may include gold bump elements and solder bump elements connected together.
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.
A solder bonding system that includes a substrate having a recess and a conductive pad having a width. The conductive pad is disposed in the recess of the substrate. The solder bonding system also includes a solder pad contacting the conductive pad. The solder pad has a width greater than the width of the conductive pad. When the solder pad is heated, it forms a stable solder bond between the conductive pads.
