PtSi contact metallurgy: Effect of silicide formation process Available to Purchase

PtSi films have been formed by different formation processes using sputtered Pt. Two annealing sequences are compared: a single‐temperature annealing at 550 °C and a three‐temperature annealing at 200–300–550 °C; and three annealing gases are compared: forming gas, nitrogen, and oxygen. Silicide films formed using the single‐temperature process all show incomplete reaction between Pt and Si, leaving a protective surface oxide layer of poor quality, which extends rather deeply into the PtSi film and is completely etched off by aqua regia. The silicide films formed by the three‐temperature process in forming gas, however, show a complete reaction between Pt and Si, and a thin surface oxide layer with excellent protection of the PtSi layer from the subsequent aqua regia etching often needed for device fabrication.