JPS6447051A - Formation of multilayer interconnection - Google Patents

Abstract

PURPOSE:To form an electrode wiring layer excellent in a step coverage in a contact hole provided to an insulating film of a multilayer interconnection by a method wherein a first electrode wiring layer formed of aluminum is subjected to a heat treatment, where melted aluminum is made to ascend up in the contact hole through the fluidity and the expansion of the melted first electrode wiring layer and the stress occurred in a second insulating film provided to the first electrode wiring layer. CONSTITUTION:A first electrode wiring layer 3 of an aluminum wiring layer is provided to a first insulating film 2, for instance, a silicon nitride film formed on a silicon substrate 1 and a second insulating film 4 is formed thereon. Next, the silicon substrate 1 is heated, where the aluminum wiring layer is made to melt to expand, aluminum ascends up in a contact hole 4a through the pressure impressed through the difference in the thermal expansion coefficient between the silicon nitride film and aluminum, and an aspect ratio is made to be small. Even when the silicon substrate decreases in temperature, aluminum in the contact hole 4a is kept in the same condition as it is because aluminum is very small in volume as compared with the first electrode wiring layer 3. Therefore, the face of a formed second electrode wiring layer 5 is made to be flat, wherefore a flat passivation film 6 is able to be formed even in the position of the contact hole 4a.