Thermal effects on the integrity of aluminum to silicon contacts in silicon integrated circuits

Serious discontinuities in aluminum interconnections at contact windows of integrated circuits have been observed with the scanning electron microscope. In some instances the discontinuities have produced catastrophic failure. Two types of discontinuities have been observed and simulation of one type has been possible through exposure to temperatures 25° to 50°C below the aluminum-silicon eutectic of 577°C. Preliminary electron probe analysis has revealed the presence of silicon in the interconnection regions overlying the silicon dioxide steps bordering the contact windows.