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High-k materials, such as HfO2, Al2O3, and many others, have been employed to replace the SiO2 insulator in the gate dielectric device in order to offer significant gate leakage reduction. In this study, the physical properties of hafnium dioxide (HfO2) thin films were analyzed and characterized in the cases of ‘as-deposited’ and ‘post-deposition annealing’ (PDA). Ultra-thin hafnium dioxide films of thickness 2.5, 5 and 10 nm were deposited on Si (100) substrates using atomic layer deposition (ALD) at temperature of 300° C. After deposition, the films were annealed using furnace in Ar ambient for 10 minutes at 450° C, 550° C, 650° C and 750° C. The thickness, density, roughness and the crystalline evolution of the HfO2 films were investigated by Grazing Incidence X-Ray Reflectometry (GIXRR) and Grazing Incidence X-Ray Diffraction (GIXRD) for both as-deposited and post-annealing conditions. Transmission Electron Microscope (TEM) was used to provide image verification of the two-layer model applied in XRR fitting analysis. Furthermore, the grain sizes were evaluated by X-ray diffraction peak-broadening (full width at half maximum, FWHM) calculation according to the Scherrer method. The experimental results showed that the annealing temperatures had significant impact on the thickness, density and roughness of the HfO2 and SiO2 layers. In addition, the experimental results demonstrated the grain sizes depend on not only the thickness of the film, but also the annealing temperatures in the crystallization process. [ABSTRACT FROM AUTHOR]

Light scattering has shown its powerful diagnostic capability to characterize optical quality surfaces. In this study, the theory of bidirectional reflectance distribution function (BRDF) was used to analyze the metallic nanoparticles’ sizes on wafer surfaces. The BRDF of a surface is defined as the angular distribution of radiance scattered by the surface normalized by the irradiance incident on the surface. A goniometric optical scatter instrument has been developed to perform the BRDF measurements on polarized light scattering on wafer surfaces for the diameter and distribution measurements of metallic nanoparticles. The designed optical scatter instrument is capable of distinguishing various types of optical scattering characteristics, which are corresponding to the diameters of the metallic nanoparticles, near surfaces by using the Mueller matrix calculation. The metallic nanoparticle diameter of measurement is 60 nm on 2 inch thin film wafers. These measurement results demonstrate that the polarization of light scattered by metallic particles can be used to determine the size of metallic nanoparticles on silicon wafers. [ABSTRACT FROM AUTHOR]