Effect of a Ge interlayer on the high-temperature behavior of NiSi films

摘要

The effect of a thin Ge interlayer on the formation of Ni silicides on (100)Si substrates has been investigated. X-ray diffraction shows a remarkable increase of the nucleation temperature of NiSi_(2) in the presence of the Ge interlayer. Four-probe measurements show that the sheet resistance of silicide formed in Ni/Ge/Si system remains stable up to 850℃, while the sheet resistance of silicide formed in Ni/Si system presents a significant increase at 750℃. Scanning electron microscopy indicates that island formation is not observed in the NiSi film grown on Ge/Si substrate annealing at 800℃. The classical nucleation theory is employed to explain the increased temperature of the nucleation of NiSi_(2) in the Ni/Ge-Si system.