In this paper, the effect of TiN metal gate deposition conditions on the crystal orientation and size of TiN grains has been investigated. We have focused on process conditions that reduce the grain size or provide a unique orientation, which might impact CMOS threshold voltage variability. We have shown that the grain size can be significantly modulated by the RF power and pressure, with grain size as low as 5.2 nm. Further it has been shown that for a few optimized conditions, a unique grain orientation can be obtained. Then, the impact of these process conditions on TiN gate mechanical stress and electrical properties has been investigated. Mechanical stress and sheet resistance are modulated by pressure and RF power and have been correlated to the deposition rate and TiN grain size respectively. The effect of TiN process conditions on MOS capacitor effective workfunction (WFeff) has been investigated, and the trend is opposite to the expected modulation of the intrinsic TiN metal gate workfunction with grain orientation. On the contrary, WFeff variation is well correlated to the Ti/N ratio, suggesting an effect related to dipole at the SiO2/high-k interface.

Density multiplication of patterned templates by directed self-assembly (DSA) of block copolymers (BCP) stands out as a promising alternative to overcome the limitation of conventional lithography. Using the 300mm pilot line available in LETI and Arkema’s materials, the main objective is to integrate DSA directly into the conventional CMOS lithography process in order to achieve high resolution and pattern density multiplication at a low cost. Thus we investigate the potential of DSA to address contact and via level patterning by performing either CD shrink or contact multiplication. Our approach is based on the graphoepitaxy of PS-b-PMMA block copolymers. Lithographic performances of block copolymers are evaluated both for contact shrink and contact doubling. Furthermore, advanced characterization technics are used to monitor in-film self-assembly process. These results show that DSA has a high potential to be integrated directly into the conventional CMOS lithography process in order to achieve high resolution contact holes.

In this work, hydrophobic mesostructured organosilica thin films, exhibiting isolated mesopores (~ 7 nm), have been successfully deposited by spin-coating using different polystyrene-block-polyethylene oxide copolymers (PS-b-PEO) as structure-directing agents and methyltriethoxysilane (MTES) as organosilica precursor. Different ordered mesostructures (Face Centered Cubic, 2D or 3D Hexagonal and Body Centered Cubic) can be achieved by controlling different synthesis parameters. X-Ray Diffraction (XRD) and Grazing Incidence Small Angle X-Ray Scattering (GISAXS) techniques were used to investigate the mesostructure evolution through thermal and UV treatments. Swelling and shrinkage were evidenced by in-situ XRD and X-Ray Reflectivity measurements during the thermal removal of the meso-templates. Infrared spectroscopy and 29Si NMR were additionally used to investigate the microstructure evolution. The film porosity was estimated thanks to Ellipsometry Porosimetry (EP). Correlation between mechanical properties through nanoindentation measurements and the mesostructure ordering is discussed as well as assessments of the dielectric constant k by mercury contact probe.

X-ray diffraction was recognized from the early days as highly sensitive to atomic displacements. Indeed structural crystallography has been very successful in locating with great precision the position of atoms within an individual unit cell. In disordered systems it is the average structure and fluctuations about it that may be determined. In the field of mechanics diffraction may thus be used to evaluate elastic displacement fields. In this short overview we give examples from recent work where x-ray diffraction has been used to investigate average strains in lines, films or multilayers. In small objects the proximity of surfaces or interfaces may create very inhomogeneous displacement fields. X-ray scattering is again one of the best methods to determine such distributions. The need to characterize displacement fields in nanostructures together with the advent of third generation synchrotron radiation sources has generated new and powerful methods (anomalous diffraction, coherent diffraction, microdiffraction, …). We review some of the recent and promising results in the field of strain measurements in small dimensions via X-ray diffraction.

Mechanical stress and stress evolution in interconnections may cause reliability problems in IC circuits. It is thus of great importance to understand the origin of this stress.

In this paper, the stress evolution during the solid state reaction between blanket titanium and aluminum films has been studied by in-situ substrate curvature measurements. Whereas the formation of TiAl3 is expected to induce large tensile stress because of a global volume decrease of 6-8%, curvature measurements of titanium/aluminum dual layers during annealing at 450°C suggests the formation of a compressive compound.

The evolution of the average force per unit width of the layer during the solid state reaction is interpreted on the basis of a phenomenological model used to describe stress evolution during silicide formation.