Aluminum-germanium-copper (Al-Ge-Cu) alloy is investigated as an interconnect material to fill contact holes and vias using low-temperature reflow sputtering. The Al-Ge-Cu has a lower melting point than conventional Al alloys such as Al-Si-Cu. The reflow temperature for contact- and via-filling decreases as the Ge concentration increases. The optimum Ge concentration for reflow sputtering at around 400 degrees C is 1 weight percent of Ge. The electromigration characteristics for stacked structures TiN/Al-Ce-0.5% Cu/TiN/Ti are investigated and compared with those for TiN/Al-1%Si-0.5%Cu/TiN/Ti. The Cu contained in Al-Ge-Cu is found to increase the electromigration lifetime because of the ill-Cu intermetallic compound formed at the grain boundaries during reflowing. It is also found that Al-1%Ge-0.5%Cu reacts with TiN during reflowing and Al-Ti-Ge intermetallic compounds, but not Ge precipitates, are formed at the grain boundaries, while Si nodules are formed in Al-1%Si-0.5%Cu without reflowing. Electromigration lifetime for Al-1%Ge-0.5%Cu is comparable to that for Al-1%Si-0.5%Cu for wide test patterns and is longer for narrow patterns.