STRESSES IN THIN-FILM METALLIZATION

Stresses in conductors used in microelectronic interconnections are a critical processing and reliability issue, This work examines: 1) the temperature dependent stress behavior of sputtered and electroplated s ilver and gold films on silicon substrates; 2) the use of wafer curvat ure using multiple substrates for the simultaneous determination of co efficient of thermal expansion (CTE) and modulus for thin films. The s tress-temperature behavior of gold films on gallium arsenide and alumi num substrates was measured to determine its CTE and modulus, It is sh own that electroplated noble metal films have lower stresses than sput tered films, due to larger grain sizes.