In this work terbium scandate thin films have been deposited by atomic layer deposition (ALD) on SiO 2/Si and Si 3 N 4/SiO 2/Si stacks and their structural and electrical behavior as a function of annealing temperature has been investigated. Films were grown using β-diketonate-based precursors and ozone at 300 C. The film crystallization in the cubic phase is induced as film thickness increases and enhanced by thermal annealing. The thermal stability of ALD TbScO x films and of their interfaces with SiO 2 and Si 3 N 4 is preserved after thermal treatment at 600 C, and their electrical characterization shows well-shaped capacitance-voltage curves, from which ak value of 16-18 is extracted. Annealing at 900 C largely affects the TbScO x/SiO 2 interface, causing the formation of an intermixed layer and silicon diffusion in the film resulting in a reduction of its k value down to 12. On the contrary TbScO x/Si 3 N 4 stack …