Nucleation and crystal growth in HfO2 thin films by UV nanosecond pulsed laser annealing

Abstract

Non-doped HfO2 thin films were annealed by UV nanosecond pulsed laser annealing. A cumulative laser irradiation effect, improving both HfO2 crystallinity and relative permittivity, was experimentally demonstrated. Interestingly, the laser-annealed HfO2 films consisted of many small grains, which were progressively aligned with their neighbors with the increase of the number of laser irradiation. These results suggest possible nucleation and crystal growth of an intentionally selected HfO2 phase by controlling the thermal budget of the single laser irradiation, which would stimulate the application of UV nanosecond pulsed laser annealing on high-k and ferroelectric Hf-based dielectrics engineering.