Lanthanum Lutetium oxide integration in a gate-first process on SOI MOSFETs

The chemical reactions at the higher-k LaLuO
₃
/Ti
₁
N
_X
/poly-Si gate stack interfaces are studied after high temperature treatment. A Ti-rich TiN metal layer degrades the gate stack performance after high temperature annealing. The gate stack containing TiN/LaLuO
₃
with a near stoichiometric TiN layer is stable during 1000 °C, 5s anneals. Both electrical and structural characterization methods are employed to explore the thermal stability of the gate stack. Based on these results an integration of TiN/LaLuO
₃
in a gatefirst MOSFET process on SOI is shown.