HfO2 films were deposited via Hf(OtBu)4 precursor and ozone oxidant using atomic layer deposition (ALD) atop Al2O 3. We report the impact of annealing conditions on the physical and electrical properties of a HfO2 on Al2O3 /SiN/Si substrate using medium-energy ion scattering spectroscopy, high-resolution transmission electron microscopy, thermal desorption spectra, and electrical measurements. Annealing temperatures influence the microstructure and impurity levels of Hf(OtBu)4HfO2/Al2O 3/SiN films. The leakage currents of Al2O 3-HfO2 bilayer were decreased with the increase of annealing temperature and the structures of the bilayer did not break until 850°C. This change was closely related to the reduction of carbon and organic contamination during annealing. However, annealing at 950°C drastically degraded electrical properties due to the intermixing of the HfO2-Al2O3 bilayer structure.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Materials Science(all)
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering