Formation of Er‐germanosilicide films on strained Si1−xGex with different Ge contents

Er-germanosilicide [Er(Si1−zGez)2−y] films were formed on strained Si1−xGex layers with different Ge contents (x = 0.14 and 0.28), and their dependency of formation kinetics on the Ge concentrations was investigated while minimizing the oxygen-incorporation effect using a TaN capping layer. When a ~30 nm-thick Er film was used, uniform Er(Si1−zGez)2−y films were obtained at an annealing temperature of around 600 °C without their agglomeration and also the strain relaxation of the remaining Si1−xGex layer. The increase in the Ge concentration of the reacting Si1−xGex layer enhanced the formation of the crystalline Er(Si1−zGez)2−y film. Furthermore, some enrichment of the Ge content within the Er(Si1−zGez)2−y film occurred in comparison with that in the initial and remaining Si1−xGex layers.