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In order to continue scaling metal oxide semiconductor field effect transistors (MOSFETs) with HfO2 gate oxides, efforts are being made to further improve the deposited high‐k film properties. Recently, a process whereby an HfO2 film is deposited through a series of depositions and anneals (so‐called DADA process) has been shown to result in films that give rise to MOS capacitors (MOSCAPs) which are electrically scaled compared to MOSCAPs with HfO2 films that only received post deposition anneals (PDA) or no anneals. We have measured as‐deposited, DADA and PDA HfO2 films using four measurement techniques, all of which are non‐destructive and capable of being used for in‐line processing, to evaluate their crystallinity and crystalline phases. Grazing incidence in‐plane X‐ray diffraction was used to determine the crystalline phases of the HfO2 films. We observed the crystalline phases of these films to be process dependent. Additionally, X‐ray and UV photoelectron spectroscopy were used to show the presence...

X‐ray scattering is a non‐destructive analytical technique capable of detecting electron density fluctuations in mesoporous and nanoporous structures. X‐ray methods have the potential to provide fully quantitative porosity analyses of open and closed pore structures. Specular x‐ray reflectivity (XRR) offers accurate measurement of thickness, density, and roughness of uniformly deposited thin films. Diffuse scattering techniques are also studied by manipulation of the scattering geometry and approximation of the average pore size and pore size distribution. Effects of refraction and reflection from the surface and buried interface are corrected via the Distorted Wave Born Approximation (DWBA). Distortion of the scattering profile due to slit smearing is also taken into account to obtain an accurate interpretation of diffuse scattering phenomena. Preliminary results for average pore size and pore size distribution of PECVD‐prepared SiCOH thin films with both open and closed pore structures are reported, and show good agreement with positron annihilation lifetime spectroscopy (PALS) data.

Dynamical X‐ray diffraction theory is extensively used to evaluate the structure of single crystal materials, where information on composition and strain can be extracted from high resolution rocking curves. Many critical materials and structures (lattice‐mismatched semiconductor heterostructures, or materials modified by ion implantation processing) may contain process‐induced structural defects and cannot be modeled by conventional perfect crystal dynamical theory approaches. Statistical dynamical diffraction theory (SDDT) incorporates both incoherent (kinematical and diffuse) and coherent (dynamical) scattering. Treatments of the SDDT theory are typically mathematically intensive while lacking instructions on how to actually implement the theory in practice. This paper discusses the implementation of the SDDT and modifications that allow for successful SDDT analyses of fully relaxed SiGe on Si.

Variable angle spectroscopic ellipsometry (VASE) measurements from 30 μm (infrared) to 150 nm (vacuum ultraviolet) were used to measure the thickness, pore volume fraction, gradation in the refractive index and chemical bonding of porous low‐κ films. The VUV spectroscopic ellipsometry measurements were used to determine the pore volume fraction and gradation in the refractive index of the porous low‐κ films. Bruggeman’s effective medium approximation was used to calculate the total pore volume fraction. The IR spectroscopic ellipsometry measurements were used to characterize the chemical bonding of the porous low‐κ samples. Absorption coefficients in the IR wavelength were used to characterize the chemical bonding in the porous low‐κ films.