Interaction of titanium with single crystal silicon during rapid electron beam heating

Abstract

The formation of titanium disilicide by the solid phase reaction of titanium with single crystal silicon has been studied using an electron beam heating method which gives well-controlled, rapid time-temperature cycles. Rapid heating of titanium coated silicon in the temperature range 750–1000 °C gives rise to titanium disilicide films having a low value of resistivity of about 15 μΩ cm. It is also reported that heating at relatively high temperatures does not preclude the formation of metastable titanium disilicide phases. Auger electron spectroscopy combined with Ar+ ion sputter depth profiling of samples, which had been exposed to a number of different heat cycles, revealed that impurities such as oxygen and carbon, adsorbed in the titanium films, are driven towards the top surface. Cross-sectional transmission electron microscopy analysis of a fully reacted sample showed that rapid heating resulted in a smooth interface between the silicide and the silicon substrate.