Trends of structural and electrical properties in atomic layer deposited HfO2 films

Understanding and optimizing electrical and structural properties of high-κ oxides are key steps in view of their application as SiO2 substitutes in CMOS devices. In this work, we address the effects of growth temperature (Tg,) post-deposition annealing and substrate preparation on the structural, compositional, and electrical properties of thin films (≈13 nm thick), deposited on p-type Si(1 0 0)/SiO2 (chemical oxide) by atomic layer deposition (ALD). In particular, we investigate the effects of: (1) different Tg (150, 250 and 350 °C); (2) rapid thermal annealing at 950 °C in N2 for 60 s; and (3) substrate in situ heat treatment before growth and longer pulses at the beginning of the deposition.