Self‐Aligned Titanium Silicided Junctions Formed by Rapid Thermal Annealing in Vacuum

Abstract

New self‐aligned silicided junctions have been developed by rapid thermal annealing in vacuum for applications to VLSI technology. These silicided junctions were investigated in regard to sheet resistance, junction depth, junction leakage current, and impurity depth profiles. After Ti film (35 nm) was deposited by dc magnetron sputtering, Si+ was implanted for interface mixing and rapid thermal annealing (RTA) in vacuum (∼10−1 Pa) were performed in temperature range of 550°–750°C. In these temperature ranges, the lateral growth of titanium silicide was prevented. After Si+ implantation through the titanium silicide layer to amorphize the Si substrate, As+ and B+ ions were implanted for n+/p junction, and p+/n junction, respectively. Finally furnace annealing (900°C, 30 min) was performed with a cap CVD oxide. We have successfully fabricated the silicided junctions with the junction depth of 0.12 μm, and the leakage current of (at reverse bias of 5.0V) for n+/p junction and of 0.14 μm, and of for p+/n junction.