The effect of Co incorporation on electrical characteristics of n+/p shallow junction formed by dopant implantation into CoSi2 and anneal

The impact of Co incorporation on the electrical characteristics has been investigated in n(+)/p junction formed by dopant implantation into CoSi2 and drive-in anneal, The junctions were formed by As+ (30 or 40 keV, 1 x 10(16) cm(-2)) implantation into 35 nm-thick CoSi2 followed by drive-in annealing at 900 degrees C for 30 s in an N-2 ambient. Deeper junction implanted by As+ at 40 keV was not influenced by the Co incorporation. However, for shallower junction implanted by As+ at 30 keV, incorporation of Co atoms increased its leakage current, which were supposed to be dissociated from the CoSi2 layer by silicide agglomeration during annealing, The mechanism of such a high leakage current was found to be Poole-Frenkel barrier lowering induced by high density of Co traps.