Metal-induced crystallization (MIC) of amorphous Si1-xGe x (x=0.2 and 0.3) thin films on SiO2 by rapid thermal annealing (RTA) at 300-600°C has been investigated. At low annealing temperature, Ni reacted with a-Si1-xGex films to form Ni germanosilicides. The crystallization temperature of a-Si0.7Ge 0.3 and a-Si0.8Ge0.2 was lowered from 500 to 400°C and 600 to 500°C, respectively, with capping Ni. The Ni germanosilicide grains were observed to form in the annealed Ni/a-Si 0.7Ge0.3 and Ni/a-Si0.8Ge0.3 samples after annealing at 500°C. The formation of island structure containing a small amount of Ge at the bottom of polycrystalline Si1-xGe x films is attributed to the preferential reactions of Ni with Si to Ge.
- Metal-induced crystallization
- Ni germanosilicides