Impact of post deposition annealing in O2 ambient on structural properties of nanocrystalline hafnium oxide thin film

Abstract

In the present work, HfO 2 thin film (100nm) has been deposited by sputtering technique and annealed at

Investigation of HfO2 Thin Films on Si by X-ray Photoelectron Spectroscopy, Rutherford Backscattering, Grazing Incidence X-ray Diffraction and Variable Angle Spectroscopic Ellipsometry

“…By the Scherrer formula, the crystallite size of HfO2 thin film of S2 and S3 with different incident angles can be calculated using the m(−111) peak of the monoclinic phase [47][48][49].…”

“…where D is the crystallite size, λ is the X-ray wavelength of Cu Kα (0.15418 nm), k is the Scherrer constant of the order of unity (0.95 for powder and 0.89 for film), β is the full width of peak at half maximum intensity (FWHM), and θ is the corresponding Bragg diffraction angle [47][48][49]. Figure 7 exhibits the m(−111) peak patterns of monoclinic phase of S2 and S3 with incident angles of 0.5°, 1°, 3° and 5°, from Figure 6b,c, respectively.…”

“…Generally, the crystal lattice with dwindling crystal size tends to generate phases of higher symmetry [50,51]. These correspond to the appearance of tetragonal and By the Scherrer formula, the crystallite size of HfO 2 thin film of S2 and S3 with different incident angles can be calculated using the m(−111) peak of the monoclinic phase [47][48][49].…”

Ultraviolet optical properties and structural characteristics of radio frequency-deposited HfO2 thin films

“…However, the mobility transition should be weak, increasing the film density and reducing the optical adsorption. After annealing, the thickness decreases with the lattice contraction for effectively passivated hafnium dangling bonds in power range from 160 W to 200 W [36,37]. And in power range of 220−240 W, thickness of annealed film increases slightly due to oxygen diffusion and crystallite size increases in annealed HfO x thin film [36].…”

“…3 (a) and (b), as the sputtering power increases from 160 W to 200 W, the O/Hf ratio falls from about 1.7 to 1.4 and the growth rate increases from 3.0 nm/s to 6.2 nm/s, while the refractive index decreases, signifying that the film has less optical density. This result is due to surface dipole repulsion, which implies dominant repulsive force between Hf 4+ atoms and therefore reduction in oxygen atom [36]. In addition, the increasing proportion of nonstoichiometric HfO x (x<2) with broken Hf−O bonds reduces the average dispersion energy parameter, which results in the reduction of refractive index in disordered HfO 2 films [15,20,38].…”