ALD Hf O2 films fabricated by a novel multi deposition multi annealing(MDMA) technique are investigated, we have included samples both with and without a Ti scavenging layer. As compared to the reference gate stack treated by conventional one-time deposition and annealing(D&A), devices receiving MDMA show a significant reduction in leakage current. Meanwhile, EOT growth is effectively controlled by the Ti scavenging layer.This improvement strongly correlates with the cycle number of D&A(while keeping the total annealing time and total dielectrics thickness the same). Transmission electron microscope and energy-dispersive X-ray spectroscopy analysis suggests that oxygen incorporation into both the high-k film and the interfacial layer is likely to be responsible for the improvement of the device. This novel MDMA is promising for the development of gate stack technology in a gate last integration scheme. ALD Hf O2 films fabricated by a novel multi deposition multi-annealing (MDMA) technique are investigated, we have included samples both with and without a Ti scavenging layer. As compared to the reference gate stack treated by conventional one-time deposition and annealing (D & A ), devices receiving MDMA show a significant reduction in leakage current. However, EOT growth is effectively controlled by the Ti scavenging layer. This improvement strongly correlates with the cycle number of D & A (while keeping the total annealing time and total dielectrics thickness the same) . Transmission electron microscope and energy-dispersive X-ray spectroscopy analysis suggests that oxygen incorporation into both the high-k film and the interfacial layer is likely to be responsible for the improvement of the device. This novel MDMA is promising for the development of gate stack technology in a gate last integration scheme.