Defect Generation during Epitaxial CoSi2 Formation Using Co/Ti Bilayer on Oxide Patterned (100)Si Substrate and Its Effect on the Electrical Properties

Abstract

Self‐aligned formation of epitaxial , using a Co/Ti bilayer, on linear oxide patterned (100)Si substrates has been investigated. Rapid thermal annealing (RTA) at 550°C resulted in lateral encroachment of silicide at the Si under the edge of the oxide. After RTA at 900°C, even though an epitaxial layer was formed on the Si substrate, defects such as lateral encroachment and void were generated under the edge of the oxide. It was found that such defects yield device failures due to deterioration of the gate oxide and the shallow junction.