FORMATION MECHANISMS OF THE DEFORMED OXIDE LAYER IN A TUNGSTEN POLYCIDE STRUCTURE

Destructive oxidation mechanisms in a tungsten polycide structure were investigated. In the experiments, the dependencies of the variation i n the process flow, structural variations and annealing temperature ap plication on the formation of destructive oxidation were examined. Sur face and structural analyses were performed using a variety of analyti cal techniques such as transmission electron microscopy. The deformed oxide layer, having a pathological morphology of the oxide surface, wa s formed on the silicide layer during the oxide process after the remo val of the surface layer of silicon oxide that initially covered the c rystallized silicide film. It was revealed that destructive oxidation resulted from the formation of volatile metal-oxides, which originated during the process of low temperature annealing in ambient O-2.