We study the charge transport mechanism in ferroelectric Hf 0.5 Zr 0.5 O 2 thin films. Transport properties of the leakage currents in Hf 0.5 Zr 0.5 O 2 are described by phonon-assisted tunneling between traps. Comparison with transport properties of amorphous Hf 0.5 Zr 0.5 O 2 demonstrates that the transport mechanism does not depend on the crystal structure. The thermal trap energy of 1.25 eV and optical trap energy of 2.5 eV in Hf 0.5 Zr 0.5 O 2 were determined based on comparison of experimentally measured data on transport with simulations within phonon-assisted tunneling between traps in dielectric films. We found that the trap density in ferroelectric Hf 0.5 Zr 0.5 O 2 is slightly less that one in amorphous Hf 0.5 Zr 0.5 O 2 . A hypothesis that oxygen vacancies are responsible for the charge transport in Hf 0.5 Zr 0.5 O 2 is confirmed by electronic structure ab initio simulation
