In this work the reverse bias junction leakage was studied for Co-silicided 100 nm deep As source/drain junctions. The effect of pre-clean and silicidation temperature was investigated. The area component of the leakage current was found to be dominant for silicided source/drain areas wider than 1 mm. Increasing the thermal budget for silicidation was found to improve the area leakage. For diodes consisting of active area stripes narrower than 0.5 μm, the leakage current is no longer improved by increasing the silicidation temperature. As a result the leakage current is found to depend strongly on the active area linewidth. It was found that the linewidth dependence of the junction leakage cannot be attributed to silicide induced stress. It is argued that the higher leakage current observed for narrow lines can be attributed to the stress induced by the STI isolation and to increased silicide thickness in the narrow active lines