Reduction of the C54-TiSi2Phase Formation Temperature Using Metallic Impurities

Abstract

AbstractThe effects of small concentrations of metallic impurities have been studied in conjunction with the formation of titanium disilicide. We report that, by introducing small quantities of a refractory metal such as molybdenum or tungsten at or near the titanium/silicon interface, the temperature required to form the C54 phase TiSi2can be reduced by as much as 100°C. Furthermore, the resulting C54-TiSi2film exhibits small (∼ 0.2μm) grain size and improved thermal stability. This discovery has the potential to reduce the complexity and cost associated with forming low resistivity TiSi2on submicron structures and to significantly improve the titanium silicide process window for future sub-half-micron VLSI applications.