Formation of Ni germano-silicide on single crystalline Si/sub 0.3/Ge/sub 0.7//Si

We have studied the Ni and Co germano-silicide on Si/sub 0.3/Ge/sub 0.7//Si. The Ni germano-silicide shows a low sheet resistance of 4-6 /spl Omega///spl square/on both P/sup +/N and N/sup +/P junctions, which is much smaller than Co germano-silicide. In addition, small junction leakage currents of 3/spl times/10/sup -8/ A/cm/sup 2/ and 2/spl times/10/sup -7/ A/cm/sup 2/ are obtained for Ni germano-silicide on P/sup +/N and N/sup +/P junctions, respectively. The good germano-silicide integrity is due to the relatively uniform thickness as observed by cross-sectional TEM.