INTERFACIAL REACTIONS AND ELECTRICAL CHARACTERISTICS IN TI SIGE/SI(100) CONTACT SYSTEMS/

Schottky barrier heights (SBH's), contact resistivities and solid-phas e reactions at the interface of Ti/Si0.8Ge0.2/Si(100) systems have bee n investigated. At annealing temperatures below 300 degrees C, Ti atom s react with Si atoms preferentially. Germanium atoms start to react a bove 400 degrees C and the formation of C54-Ti(Si0.88Ge0.12)(2) is con firmed by X-ray diffraction after annealing at 650 degrees C. The anne aling behavior of SBH's suggests that Ge atoms are segregated in SiGe layers at the interface, which is consistent with the results on inter facial reactions. For both n- and p-SiGe, the lower SBH's than Ti/Si(1 00) are obtained at 650 degrees C, which is considered to he due to th e work Function of reaction products such as C54-Ti(Si1-yGey)(2). The contact resistivities smaller than those expected from the SBH's are o btained for n(+)- and p(+)-SiGe at 580 degrees.