Journal
JOURNAL OF CRYSTAL GROWTH
Volume 312, Issue 2, Pages 245-249Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.jcrysgro.2009.10.028
Keywords
Atomic layer deposition; Chemical vapor deposition processes; Dielectric materials; Oxides
Funding
- Academy of Finland [128805, 125301]
Ask authors/readers for more resources
HfO2 thin films were grown at temperatures between 250 and 400 degrees C by atomic layer deposition using novel cyclopentadienyl-alkylamido precursors, namely CpHf(NMe2)(3) and (CpMe)Hf(NMe2)(3) (CP, cyclopentadienyl = C5H5). Ozone was used as the oxygen source. The self-limiting growth mode was verified at 300 degrees C with a growth rate of 0.7-0.8 angstrom/cycle, depending on the precursor. Thermal decomposition started to have an effect on the growth mechanism at temperatures near 350 degrees C. As compared to the widely applied Hf(NEtMe)(4) precursor, these novel precursors with higher thermal stability resulted in HfO2 films with lower impurity contents. The carbon and hydrogen contents below 0.5 and 1.0 at.%, respectively, were characterized for films deposited at 300 degrees C from both novel precursors. The 50-nm-thick HfO2 films deposited at 300 degrees C or above were crystallized in mixture of monoclinic and cubic or tetragonal phases. Doping with low amounts of yttrium and subsequent annealing of 7-nm-thick film on TiN stabilized the preferred high-permittivity cubic or tetragonal phases, resulting in low capacitance equivalent thickness and leakage current density. (C) 2009 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available